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"Why do I still live? What more do you want from me? I gave everything I had to you, to them. Look what they've made of our dream. This bloated, rotting carcass of an empire is driven not by reason and hope but by fear, hate and ignorance. Better that we had all burned in the fires of Horus' ambition than live to see this."

—Roboute Guilliman, primarch of the Ultramarines, reflecting upon the state of the Imperium of the 41st Millennium and his devotion to the Emperor of Mankind
Roboute Guilliman Avenging Son

Roboute Guilliman, primarch of the Ultramarines Legion and lord of Ultramar at the time of the Great Crusade.

Roboute Guilliman (pronounced Ruh-BOOT-ay GIL-li-man), sometimes referred to as the "Avenging Son," "The Victorious," "The Master of Ultramar" and "The Blade of Unity," is the primarch of the Ultramarines Space Marine Legion and its myriad subsequent Successor Chapters. He is the current lord commander of the Imperium and the ruling Imperial Regent.

Held by some as a paragon among the Emperor's sons, Roboute Guilliman was as much a patrician statesman and empire-builder as he was an indefatigable warrior.

A being of preternatural intelligence, cold reason and indomitable will, Guilliman forged his XIIIth Legion into a vast force of conquest and control, a weapon by which he made himself the master of a stellar domain in the Eastern Fringe of the galaxy, the Realm of Ultramar, which during his lifetime spanned five hundred worlds.

Before He began His conquest of the galaxy, the Emperor of Mankind created the primarchs. Utilising incredible skills at genetic engineering, and the phenomenal psychic power bound into His own form, He forged twenty demigod sons. These were superlative transhuman warriors, strategists and leaders, the finest qualities of Humanity refined in the crucible of science and magnified through the lens of divinity.

The Emperor intended the primarchs to stand at His side during the Great Crusade, each leading one of the twenty Space Marine Legions to glory beyond imagination.

Before that plan could come to pass, the Dark Gods of Chaos intervened. They snatched up the nascent primarchs and scattered them through the Warp, so that each came to rest upon a different one of Humanity's far-flung worlds. Some say that it was at this time that the Ruinous Powers left their mark upon the Emperor's gene-sons, and that this is why fully half of the primarchs betrayed their father and the Imperium during the Horus Heresy.

Whatever the case, Roboute Guilliman was not tainted in such a fashion. The being that would become the primarch of the Ultramarines Legion came to rest upon the world of Macragge. There he was discovered, and adopted, by a local warlord named Konor. Growing and developing at a superhuman rate, Konor's adoptive son soon surpassed all those around him, and came to be the greatest warrior, strategist and statesman upon Macragge.

After Konor was slain by a treacherous ally, it was Guilliman who avenged his foster father, before taking upon himself the mantle of kingship. The entirety of Macragge was swiftly unified beneath the banner of Roboute Guilliman, becoming a world of peace, civilisation, wisdom and strength.

Guilliman was a charismatic and gifted leader, beloved of his people and singularly capable of compartmentalising incredible quantities of information. He was an organiser, a logistician, one capable of turning the wildest theories into practical reality and rendering order from chaos.

When the Emperor's crusading forces finally reached Macragge in the late 30th Millennium, the son was reunited with his true father. Guilliman was given charge of the Ultramarines Legion, and wasted no time in putting his stamp upon it. In the conquests that followed, the Ultramarines became renowned as exemplars of what it meant to be a Space Marine.

Under Guilliman's leadership they became arguably the most strategically gifted and tactically balanced of all the Legiones Astartes. Working on the basis of theoretical situations and practical solutions, the Ultramarines fought with exceptional efficiency. They drove the foes of Humanity before them, their armies fighting like intricate and perfectly tuned machines to swiftly and decisively outmanoeuvre every foe.

When the Horus Heresy set the galaxy ablaze, Roboute Guilliman fought with loyalty and determination for the Imperium that he believed in with all his heart. When he thought that the Emperor had fallen, the primarch established a new seat of power on Macragge, planning to preserve the Emperor's secular purity and Imperial Truth within his own Realm of Ultramar as the Imperium Secundus.

When Guilliman later learned that Terra still stood, he did everything in his power to ensure that he and his loyal brothers could fight at their father's side in the final battle against Horus. Though his efforts benefitted many, Guilliman himself reached Terra too late, a fact that would torture him for solar decades to come.

In the wake of the Horus Heresy, it was the Ultramarines primarch who wrote and instituted the Codex Astartes, a key volume that laid out the proper tactics and military organisation for the majority of Loyalist Space Marine Chapters now in existence.

Guilliman is the primarch who took up the Emperor's burning blade and became the lord commander of the Imperium and the Imperial Regent, serving amongst the High Lords of Terra during the period of the reformation and reconstruction of the Imperium's administrative and military structure called the Time of Rebirth. Guilliman single-handedly reshaped the Imperium after the Horus Heresy, taking the lead role in reforming its bureaucratic and military apparatus following the internment of the Emperor of Mankind within the Golden Throne on Terra.

Roboute Guilliman is also one of the few Loyalist primarchs still alive. Following the Great Scouring, Guilliman and his Ultramarines met the Emperor's Children Traitor Legion at the Battle of Thessala in 121.M31, where his corrupt brother Fulgrim mortally wounded him with a slice to the neck made by that Daemon Primarch's Chaos-tainted blades.

So it was that the dying Roboute Guilliman was put into temporal stasis on the verge of death and his body placed upon the throne that lay in the Temple of Correction on the Ultramarines' homeworld of Macragge. For the last ten millenia many pilgrims of the Imperial Cult travelled across the galaxy every standard year to visit the temple and see the body of a primarch, a blessed son of the God-Emperor Himself.

Some pilgrims claimed that the grievous wound was slowly healing, though such an action was physically impossible within an activated stasis field. The Avenging Son was silently enthroned through the millennia as his father's Imperium decayed around him, waiting until such a time when one could come with the power to restore him. And that time has come.

The primarch was resurrected during the Ultramar Campaign of the 13th Black Crusade in 999.M41 by the technical prowess of Archmagos Dominus Belisarius Cawl and the power of the Aeldari god of the dead Ynnead through his priestess Yvraine.

Soon after, Guilliman launched the Terran Crusade from Macragge through the growing Warp instability of the galaxy as the power of Chaos waxed mighty once more with the birth of the Great Rift. After nearly being imprisoned for eternity in the Maelstrom and then almost slain by his brother the Daemon Primarch Magnus the Red on Luna, Guilliman finally arrived at Holy Terra.

There, he entered the inner sanctum of the Imperial Palace and met with his father the Emperor for the first time in more than ten thousand standard years. What passed between father and son at that meeting is not known, but when he emerged, Guilliman announced that he was once more assuming the mantles of the lord commander of the Imperium and Imperial Regent, the first among equals on the Senatorum Imperialis and the de facto ruler of the Imperium.

As the Great Rift's cataclysmic birth following the fall of Cadia disrupted interstellar travel and communications and the Noctis Aeterna closed like a shroud upon the galaxy, Guilliman moved swiftly to stabilise the faltering Imperium. He turned to Belisarius Cawl once more to complete a plan that had been over 10,000 standard years in the making, since the end of the Horus Heresy and Guilliman's last tenure as the Imperium's lord commander.

Cawl had spent that time "perfecting" the Emperor's original genetic template for the Space Marines laid down before the Great Crusade, creating a new legion of hundreds of thousands of improved Astartes deep beneath the surface of his forge on Mars. This new breed of transhuman warrior, the Primaris Space Marines, were bigger, more physically powerful and possessed faster reaction times than their original Astartes counterparts.

Cawl had also spent the intervening millennia pushing the very boundaries of Adeptus Mechanicus dogma in search of "innovation," creating new, more advanced power armour, wargear, and vehicles for the Primaris Marines.

But before Guilliman could move to make use of his new armies, the Chaos God Khorne took advantage of the Noctis Aeterna to launch a daemonic assault upon the Throneworld of Mankind, initiating the Battle of Lion's Gate.

Though Guilliman led the Imperial defenders, including the Sisters of Silence and the Adeptus Custodes, in throwing back the howling servants of the Blood God, the brazen assault shocked the High Lords of Terra to the core. They realised that in this new age, no world was safe from the Ruinous Powers and the other foes of Mankind.

In the wake of the Battle of Lion's Gate, Guilliman gathered the greatest fleet of Imperial warriors that had been seen since the Great Crusade. The largest component of this force included a massive new host of hundreds of thousands of Primaris Space Marines, divided half into new Chapters of the Adeptus Astartes and half into 9 Space Marine Legion-sized formations known as the Unnumbered Sons.

The primarch launched this massive Indomitus Crusade out into the void, determined to throw back the forces of Chaos and the xenos hordes wherever they threatened the worlds of humanity. Guilliman set a winding course. Strike forces from over a dozen pre-existing Chapters of Space Marines, led by the Imperial Fists, also joined the fleet. Thus began many new legends as Guilliman travelled to aid beleaguered planets, breaking sieges and sweeping away Chaos and xenos invaders alike to bring hope back to the desperate defenders.

The Indomitus Crusade would reach the end of its first major phase approximately twelve standard years later at the Battle of Raukos. Afterwards, Guilliman would turn his attention to helping his Realm of Ultramar defeat the forces of the Death Guard Traitor Legion and the servants of Nurgle in the Plague Wars, driving his traitorous brother Mortarion and the Death Guard Traitor Legion from the region in ca. 012.M42.

Before the conflict had ended, Guilliman announced that he had made a grave mistake when he had allowed the official borders of Ultramar to shrink so drastically in the days after the Horus Heresy.

Instead, he reestablished the ancient ruling Tetrarch Council for Ultramar, and tasked its newly-appointed Tetrarchs, including his Primaris Space Marine Equerry Captain Decimus Felix and the Ultramarines First Captain Severus Agemman, with beginning to expand the territories of Ultramar to include all of the star systems that had once comprised the Five Hundred Worlds.


"The warrior who acts out of honour cannot fail. His duty is honour itself. Even his death -- if it is honourable -- is a reward and can be no failure, for it has come through duty. Seek honour as you act, therefore, and you will know no fear."

Primarch Roboute Guilliman

Son of Macragge

Guilliman Sketch

Ancient Remembrancer sketch from Carpinius' Speculum Historiale, depicting Roboute Guilliman, primarch of the Ultramarines Legion, during the Great Crusade.

Thanks to the widely distributed efforts of numerous Imperial Iterators, the story of the Primarch Roboute Guilliman, his early life and his finding is widely known and well accounted for, in stark contrast to certain others of the primarchs.

Much of these accounts have of course served the role of edification for the masses and the demands of propaganda, but between the accounts, variously embellished, a number of consistent facts and themes emerge.

According to Imperial legend, the Emperor of Mankind created the primarchs from artificially-engineered genes using His own genome as a template, carefully imbuing each of them with unique superhuman powers. Imperial doctrine goes on to tell how the Ruinous Powers of Chaos spirited away the primarchs within their gestation capsules from beneath the Imperial Palace in the Himalazian (Himalaya) Mountains on Terra, scattering them widely across the galaxy through the Warp.

More than one of the capsules was breached whilst it drifted through Warpspace -- the forces of the Immaterium leaked in, wreaking havoc on the gestating being inside the capsule. Undoubtedly damage was done and Chaotic corruption affected several of the primarchs, although the nature of that corruption would not become apparent until the Horus Heresy.

The twenty gestation capsules came to rest on human-settled worlds throughout the Milky Way Galaxy, distant planets inhabited by a variety of human cultures. Whether by fickle fate or cruel design, each world would provide a crucible which would temper the child into the primarch he would become, be that hero or monster, tyrant or liberator.

The capsule containing the developing form of one primarch fell upon the world of Macragge in the Eastern Fringe of the galaxy. Macragge was a bleak but not inhospitable world, part of a decayed star empire of ages past that Mankind had inhabited for many centuries since the time of the Dark Age of Technology.

Its industries had survived intact, and its people had retained an authoritarian but cohesive society. It had remarkably preserved a number of antiquated, short-range Warp-capable craft which could be utilised for near-stellar transit -- conditions permitting -- and its people continued to build sub-light spacecraft even during the time of the most intense Warp Storms.

This had allowed the people of Macragge to maintain contact with several neighbouring human-settled star systems, despite the storms' fury, and so retain a tenuous link to the rest of human space and the knowledge that it was not alone in the darkness.

So it was that when the primarch's fallen capsule was discovered by a group of magnates who were on a hunt in a local forest, they knew it immediately for a device of advanced technology rather than a thing of superstition and magic. The magnates broke the capsule's seal and discovered a strikingly beautiful and perfectly formed child within it who was surrounded by a glowing nimbus of power.

The child was brought before Konor Guilliman, one of a pair of nobles who bore the title "consul", whose authority governed the most civilised and powerful region of Macragge, and Konor adopted the infant as his own son in a manner not uncommon to his culture, naming him Roboute.

The young primarch grew unnaturally quickly and as he did so, his unique physical and mental powers became obvious to all. It is recorded that by the time of his tenth standard birthday, Guilliman had mastered everything the wisest tutors of Macragge could teach him.

His insight into matters of history, philosophy and science astonished his teachers, while his recall was absolute and his ability to extrapolate accurate conclusions from fragmentary information was said to border on the inexplicable.

His greatest talent, however, lay in the art of war, which was itself treated as a high and lauded science in Macragge's culture. As soon as he had attained his legal majority, Roboute's foster father Konor immediately granted him command over an expeditionary force sent to pacify the far northern lands of Macragge.

Named Illyrium, it was a barbarous land of outcasts and petty, warring micro-states that had long harboured brigands and mercenaries who raided more civilised lands as often as they hired themselves as foot soldiers to fight their neighbours' wars.

Roboute fought a brilliant campaign and won both the submission and the respect of the fierce Illyrium warrior bands, but when he returned to his home from the northern frontier, Roboute found the capital city of Macragge Civitas in turmoil.

Death of Konor

During Roboute's absence, Konor Guilliman's co-consul, a man name Gallan, had unleashed a coup d'etat against Konor -- a development far from unknown historically, if in this instance a surprise. Gallan, it transpired, had long harboured designs on undiluted rulership and had conspired with those amongst the wealthy nobility of Macragge who were jealous of Konor's political power and popularity, and also increasingly afraid of his preternaturally precocious foster child's future.

These malcontents represented Macragge's ancient regime, an aristocracy whose wealth was manifested by vast estates which were supported by the toiling of a multitude of impoverished vassals. Konor, backed by Macragge's industrial magnates -- rivals to the old regime -- had moved to challenge this balance of power, forcing the aristocracy of Macragge to provide their vassals with increased living standards and rights before the law, weakening the aristocracy's stranglehold on the polity.

Konor had also passed legislation that obliged the nobility of Macragge to begin an ambitious programme of improving the long-neglected infrastructure of their nation and enlarging the capital city at their own expense. These reforms made Konor Guilliman all but unassailable in the common people's eyes, but were highly unpopular among all but a few of the more far-sighted aristocrats.

As Roboute Guilliman and his triumphant army approached the city of Macragge Civitas, they saw the smoke from a multitude of fires and encountered citizens fleeing from the city in anarchy, and Roboute learned that Gallan's private army had attacked the senate house while Konor and his loyal bodyguard troops had been inside. The refugees each told the same story; that rebel soldiers had attacked the senate, whilst a drunken mob, instigated by Gallan but now out of anybody's control, roamed the city burning, looting and murdering.

Roboute hurried to his foster father's rescue. Leaving his own troops to deal with the drunken rioters without quarter, Roboute personally fought his way towards the centre of the city, passing the bloody work of rebel firing squads everywhere in the government district, but at the senate house, found himself too late. All was a bullet-ridden and blasted ruin, and even the rebels it seemed had fled the scene to join the looting.

There, in the half-collapsed shelters beneath the building, Roboute found his father dying. For three local days the wounded consul had directed the defence of the besieged senate house, even as surgeons fought for his life following a botched assassination attempt on the senate floor which had touched off the conspiracy's chaotic attack. It is apocryphally said that as he gasped out his last breath, Konor detailed the extent of Gallan's betrayal to his beloved foster son and named those whose hands were stained with his blood.

Roboute Guilliman's cold rage at his foster father's death was unstoppable. With the full backing of his army and the beleaguered citizens of Macragge Civitas, Roboute crushed the aristocratic rebels, scattering their hireling armies and lined the streets with the hanging bodies of the rioters, thereby quickly restoring order to the capital city and the surrounding lands.

Thousands of citizens flocked to the senate house and amidst a wave of popular acclaim, Roboute assumed the mantle of the sole and now all-powerful consul of Macragge. The new ruler broke the old, aristocratic order and stripped from them their lands and titles.

Gallan and his fellow conspirators were seized, the ring leaders publicly executed and the rest sentenced to hard labour rebuilding the city they had ruined, stone by stone, by hand. It was not a sentence they would long survive. In the new order, loyal soldiers and hardworking settlers were granted rights where the oppressive aristocracy had once held sway.

With superhuman energy and the singularity of vision only a primarch was capable of executing, the new consul reorganised the social order of Macragge, creating a ruthlessly enforced meritocracy where the hardworking prospered and the honourable received positions of high office, and those who shirked the law or worked against the good of the whole faced draconian, but faultlessly even-handed punishment.

The stagnated and uneven economy was re-ordered, technology disseminated rather than horded by the elite, and the armed forces were transformed into a powerful and well-equipped force. Macragge flourished as never before -- one people and one order, united under the people and one order, united under the unchallengeable rule of Roboute Guilliman.


Emperor -closeup

The Emperor of Mankind

Around the time that the young Roboute Guilliman waged war in Illyria, the Emperor's fleet had reached the planet of Espandor at the outer edge of the network of worlds with which Macragge had maintained tenebrous contact. From the Espandorians the Emperor learned of the existence of Macragge and the extraordinary son of the Consul Konor Guilliman, and from what He learned He knew that this child could be none other than a missing primarch.

There have been some who have suggested that the Emperor's arrival at Espandor and the isolated region so far from the frontline of the Great Crusade's main spur of progress was no accident, and that by some arts He had perceived or had foreknowledge of what He would find.

Regardless, what followed was certainly not foreseen. As the Emperor's fleet quickly moved on to Macragge in ca. 832.M30, it was almost immediately deflected by violent Warp squalls which had risen up to separate Macragge and a handful of nearby systems from approach. Thwarted by a power even the Emperor could not readily ignore, it would be something in the region of five standard years before contact could be successfully attempted.

In the years that intervened, Macragge had undergone a striking transformation. It was now a world of uniformity and order, prosperous and productive. Its cities had been rebuilt in glittering marble and shining steel, and the serried ranks of its armies were well armed and well equipped, and outfitting themselves now for operations beyond their own world.

For even before the Emperor's arrival, Roboute Guilliman, it is said, had dwelt much on the ancient histories contained from his world's deposed aristocracy, and the fragments he found there telling of the ancient domains of Mankind, and he had begun to dream of new horizons and new worlds to conquer, of a domain "beyond the seas of night" or to use the ancient scholarly form found in the text -- "Ultramar".

By his will, he made it so and within their Warp-sealed enclave, vessels from Macragge now plied regular and well-patrolled trade routes with local star systems, bringing raw materials and people to the flourishing world, while against some of its neighbours, short, victorious conflicts had already been waged to pacify the strife they had found there.

It is said that when the Emperor finally saw what His lost son had wrought in 837.M30, He was indeed pleased, and that He met with Roboute Guilliman without the dissembling that had been needed with those primarchs He had found of more savage timbre. It is further more recorded that once Guilliman learned the truth of his origins, he immediately swore his fealty to the Emperor, who he knew was his true father, for he had already theorised correctly the purpose for which he had not been born so much as deliberately created.

It was immediately apparent to Imperial observers that Roboute Guilliman possessed a powerful analytical intelligence, even when compared to the superhuman cognitive abilities of his peers, as well as talent for statecraft and macro-organisation of staggering potential. Yet few could then guess what such talents harnessed to the Great Crusade would go on to achieve.

Unification of Body and Soul

The XIII Legion of Space Marines, sometimes called the "War-Born," was assigned to Guilliman in short order, for the primarch needed little urging or aid in the assimilation of knowledge of the wider galaxy, the Great Crusade and the many technological wonders of the new-born Imperium of Man.

It was a development greeted by the XIII Legion with great rejoicing and pride in the honour that Roboute Guilliman paid them in accepting their fealty.

The oratory and vision with which their new-found primarch expounded to them his designs for the future and the righteousness of the Great Crusade filled the Legiones Astartes with a renewed vigiour and dispelled any shadows of doubt in their minds, and made Guilliman's takeover, according to official records, all but seamless.

Roboute Guilliman did far more than merely take command of the XIII Legion, he set about transforming it. His vision was for a Legion that was more than simply one army among many, however exceptional, but a self-sustaining power for conquest, order and expansion; the strength of the body and blood of the Imperium made manifest by the will of the Emperor through His servant Roboute Guilliman.

To him, a military force was more than the warriors who wielded arms -- it was their chain of supply, the ships which carried them between, the manufactora which supplied their munitions and the worlds which bred their recruits; they were indivisible and equally vital. To Guilliman's mind, all of these things made a Space Marine Legion, and he meant to control them all so that his own would prosper and the Emperor's will be done.

In accordance with his grand design, he planned to not merely take the world of his fosterage as his headquarters and recruiting ground as his peers had done and would continue to do, but from the start set it up as merely the fulcrum of a far larger network of provender and support.

The basis of this network would be the worlds Macragge had long maintained links with, but they would merely be its first components, not its fullest extent. This would be the start of Robout Guilliman's "Ultramar" and it would be a project of decades, and continue to expand right up to the first treacherous blow of the Horus Heresy.

Eagle of the East

As swiftly as he put his plans for Ultramar into action, he embarked on the root and branch reorganisation of his Legion. Adopting an extraordinarily detailed plan which drew from both the military doctrines and political philosophies of his surrogate homeworld, a detailed study of the history of the XIIIth and each and every other Legion and armed force under the Emperor's banner in their then current form, he remade the organisational structure and tactical doctrines of his Legion accordingly.

The result was an elegantly structured but elaborate and highly meritocratic force. It unsurprisingly built on much that had already been evident in the character of the XIII Legion, as their primarch's gene-seed had already partly shaped them, however unconsciously, and through the application of analysis and reason sought to purge any weaknesses or deficiencies to achieve the optimal military outcome.

This, as with so much of the Legion's affairs, was considered by the primarch an ongoing project, and it evolved quickly into a dual doctrine which embraced in parallel on one hand what were the ancient and deterministic values of the warrior: courage, discipline, skill and adaptability, defined as that which was "practical," and on the other: planning, precedent, analysis and assessment, defined as that which was "theoretical."

Both were of equal weight and value, one complementing and informing the other, blending together as the metals which made a fine blade. This became the Legion's doctrine and creed.

As with the society Roboute Guilliman had built on Macragge, the XIII Legion under his mastery would be as ruthlessly even-handed as it was efficient, with the needs of the individual sublimated to the greater whole, but the life of the individual never spent wantonly or without purpose; for the doctrine stated that each Legionary lost weakened those who remained.

Within the Legion, the valour and the achievement of the individual were rewarded with honour and responsibility, but the obedience to hierarchy and order it demanded of its members was to be unquestioning and unchallenged. The outward signs of this transformation were striking, the livery of the XIIIth was altered to a deep blue, chased with gold, while the symbol of the ancient "Ultima" glyph found in the pre-isolation stellar charts of the region was adopted as its icon and seal to tie them to the newfound realm which they embodied.

With it the cognomen "Ultramarines", perhaps as one monography attributed to Remembrancer L. Amphidal suggested, "Roboute Guilliman and his Legion would vow to take the Great Crusade beyond the stars themselves if needed to see its completion."

Great Crusade

Primarchs Bk 1 - Roboute Guilliman

Primarch Roboute Guilliman leading his Ultramarines during the Great Crusade.

With its forward base relocated to Macragge, Guilliman was granted independent crusade command for the region, and quickly set about a series of fresh conquests. His 12th Expeditionary Fleet reformed under his command and was supplied with warships of the latest designs from Mars as a boon of the Emperor.

Fresh conquests were immediate, as the newly named Ultramarines rapidly expanded their range out from Macragge, identifying suitable targets for Compliance and singling out xenos holds for eradication. Interrupted only when called upon to join larger campaigns by the will of the Emperor, for nearly a century the 12th Expeditionary Fleet ranged as far to the galactic north as the dead expanse where the Dominion of Storms ended and as far to the galactic east and south as the point of Ultima Thule, where the stars paled and emptied out into the limitless darkness of the exo-galactic void.

During this period, the Ultramarines, by some records, succeeded in liberating more worlds than any other single primarch's forces, and the planets Roboute Guilliman brought within the Imperium always benefitted from his intense passion for efficient and ordered government.

Whenever Guilliman and the Ultramarines made a world Compliant, his forces spent as much effort in establishing it afresh, setting up self-supporting defences, and ensuring that in his wake, the agents of the Imperial Truth and industry would firmly seal the world's place in the fabric of the Imperium.

This spread of cohesive civilisation in the Legion's path served both to solidify and expand supply lines for its advance, facilitating in no small part the great speed and range of the Ultramarines' conquests.

Within solar months of the Legion's establishment on Macragge, the first influx of new recruits had arrived at the Fortress of Hera, the Legion's fortress-monastery and new headquarters, and the process of renewal and increase in the XIII Legion's fighting strength had begun and never since had ceased.

Wave after wave of recruits were taken in and processed, not simply from Macragge and the surrounding worlds of the slowly expanding Ultramar, as numerous as they were, but from scores of worlds and colony outposts where the conquering fleets of Roboute Guilliman had gone.

By the time Horus was appointed Warmaster, the Ultramarines were by any official assessment the largest single Space Marine Legion by number of Legionaries with a considerable margin. Owing to this expansion, the now-massive 12th Expeditionary Fleet was sub-divided into a score of smaller expeditionary and persecution fleets, allowing the Legion to range further, each still numbering scores of vessels and thousands and sometimes tens of thousands of Legionaries.

The numeric strength of the Ultramarines Legion, in excess of 250,000 Astartes, would be an achievement that would not be surpassed, though in secrecy the late expansion of the Word Bearers, who originally numbered approximately 100,000 Astartes, would come to rival them by some assessments, while the wilder claims as to the strength of the Alpha Legion also have them run closer than official records would indicate.

This scale of military force and the near-autonomous "empire within an empire" that maintained it, Ultramar having reached a dominion popularly ascribed as the "Five Hundred Worlds" before the outbreak of war, would have dire and unforeseen consequences for the Ultramarines and their primarch.

Separate and inviolate in the east, and a great power within their own right, the Legion's very existence made them a threat to the Traitors' conspiracy that could not be ignored, and later on Calth would the Warmaster's plan and the Word Bearers' desire for revenge see that threat destroyed.

Triumph of Ullanor

In the latter years of the 30th Millennium, forces of the Imperium undertook the Ullanor Crusade, a vast Imperial assault on the Ork Empire of the Overlord Urrlak Urruk. The capital world of this greenskin stellar empire, and the site of the final assault by the Space Marine Legions, lay in the central Ullanor System of the galaxy's Ullanor Sector.

The crusade included the deployment of 100,000 Space Marines, 8,000,000 Imperial Army troops, and thousands of Imperial starships and their support personnel. The Ullanor Crusade marked the high point of the Great Crusade's vast effort to reunite the scattered colony worlds of humanity.

The Orks of Ullanor represented the largest concentration of greenskins ever defeated by the military forces of the Imperium of Man before the Third War for Armageddon began during the late 41st Millennium. Following the defeat of the Orks of Ullanor, the Emperor of Mankind was to return to Terra to begin work on His vast project to open up the Aeldari Webway for Mankind's use.

In His place to command the vast forces of the Great Crusade He left Horus. In the aftermath of the Ullanor Crusade, Horus was granted the newly-created title of "Warmaster," the commander-in-chief of all the Emperor's armies who possessed command authority over all of the other primarchs and every Expeditionary Fleet of the Great Crusade.

When the Emperor proclaimed Horus, Warmaster of the Imperium, Guilliman accepted the news without resentment, and Horus continued to seek his counsel. However, Horus believed that Guilliman felt that he had deserved the honour of being named Warmaster just as much, if not more.

Before returning to Terra to oversee the next phase of the creation of His stellar empire, the Emperor suggested to Horus that he rename the XVI Legion the "Sons of Horus," in honour of their primarch and to show his preeminent place amongst the other primarchs.

Horus initially declined this honour, not wishing to be set above his brothers, and so his Legion continued as the Luna Wolves for a little while longer. But Horus and the other primarchs never came to terms with the Emperor's absence.

Their hurt feelings over His seeming abandonment of the Great Crusade to pursue a secret project whose purpose He chose not to reveal to His sons laid the seeds of jealousy and resentment that would ultimately blossom into the corruption that begat the Horus Heresy.

Horus Heresy

Battle of Calth

"Space Marines excel at warfare because they were designed to excel at everything. Each of you will become a leader, a ruler, the master of your world and when there is no more fighting to be done, you will bend your talents to order, governance and culture so that the Imperium will stand eternal."

— Roboute Guilliman to his gathered Chapter Masters (duty servo-transcription, hours prior to the Battle of Calth
UM vs WB Calth

An Ultramarine Legionary fighting against a traitorous Word Bearer.

When the Warmaster Horus turned his back on the Imperium, swore his allegiance to the Ruinous Powers of Chaos, and began the Horus Heresy, his first act before making his break with the Emperor of Mankind open was to lure away as many Loyalist Legions from Terra as possible.

Horus ordered Guilliman to lead an expeditionary force to the world of Calth in the Veridian System in the Realm of Ultramar to prepare for a campaign in the Eastern Fringes of the galaxy, where, Horus claimed, an Ork WAAAGH! was massing.

Horus expected the Ultramarines to await the arrival of the Word Bearers who would join with the XIII Legion in prosecuting a campaign against the Ork menace. Unknown to Guilliman, the XVII Legion had long before turned Traitor in service to the Chaos Gods, and its primarch, Lorgar, gleefully accepted Horus' orders to close the trap on his Legion's long-hated rivals.

The Word Bearers' sudden attack decimated Guilliman's Legion fleet, and the Ultramarines' ground troops quickly found themselves impossibly outnumbered by their former allies as the infamous Battle of Calth erupted. The Word Bearers slew their Loyalist foes in droves in the early stages of their surprise attack and pushed them back over huge stretches of territory.

The Traitors rejoiced at the terrible blows they were inflicting upon the Legion that had once aided the Emperor in humiliating them upon the world of Khur decades before the start of the Heresy when they had been taken to task for repeated violations of the atheistic philosophy known as the Imperial Truth.

Helixus Tactical Squad

A surviving Ultramarines Tactical Squad during the Calth Atrocity.

Unknown to them, Guilliman's flagship, which had survived the initial Word Bearers' attack on the Ultramarines fleet, effected emergency repairs and regrouped with the other surviving Ultramarine starships in space. Having taken stock of his remaining forces, Guilliman sent an immediate astropathic distress call to Macragge.

The Loyalist Marines on Calth, Ultramarines all, had been forced into a fighting retreat, but soon occupied fortified positions. Many Ultramarines had been born on Calth, and proved more resolute than the Word Bearers anticipated. In space, Guilliman's vessels began hit-and-run attacks on their over-confident enemy. Guilliman assessed his ground troops' positions and broadcast clear, concise orders to each pocket of defence, coordinating them into a cohesive force.

One Ultramarine force led by Captain Ventanus led a breakout and retook Calth's Defence Laser silos, aiding the sorely-pressed Ultramarines fleet from the surface of Calth. Guilliman's depleted forces slowed the Word Bearers down long enough for the remainder of the Ultramarines Legion to arrive and rout the Traitor Marines from the system, though at a heavy cost.

The Word Bearers turned Calth's own orbital defence platforms on the Veridian star, stripping away the outer layers of its photosphere and destabilising it, ultimately rendering the surface of Calth uninhabitable. At the same time, the Word Bearers had used the battle taking place on Calth to summon a massive Warp Storm called the Ruinstorm, that was intended to cut off Ultramar from the rest of the galaxy and prevent the Ultramarines from providing any reinforcements to Terra as Horus made his assault upon humanity's homeworld.

Guilliman space battle

Roboute Guilliman, during the Battle of Calth, leading his Ultramarines against the Word Bearers.

The eruption of the Ruinstorm cut off Calth from the main body of the Ultramarines Legion and left the Astartes of the XIII Legion trapped on Calth locked in a brutal subterranean war with those Word Bearers units that had also been left behind when their Legion retreated from the Viridian System.

Yet Roboute Guilliman and a large portion of his Legion had remained off-world as a result of the Word Bearers' devious assault upon the Ultramarines fleet. Bloodied but unbowed, the Ultramarines received the orders of Malcador the Sigillite, the Emperor's Regent, while he was indisposed pursuing the secret Imperial Webway Project, and prepared to meet the needs of the Imperium's defence against the Traitor Legions as best they could.

Shadow Crusade

In his wrath, the Lord of Ultramar had gathered what vessels he could spare after Kor Phaeron's ambush, drawn additional numbers from the first Ultramarines relief fleet bound for Calth after the massacre above that world, and tracked Lorgar directly through the use of the XIII Legion's own astropathic choirs.

In the wake of the Battle of Calth, the Word Bearers Legion, led by Lorgar, linked up with Angron and his World Eaters Legion to launch a Shadow Crusade against the Realm of Ultramar's Five Hundred Worlds in an attempt to spread the massive Warp Storm known as the Ruinstorm that had been conjured by the Word Bearers' First Chaplain Erebus at Calth across the Eastern Fringe.

This prodigious Warp Storm would effectively split the galaxy in half and deny needed reinforcements to the Loyalists as Horus drove on Terra in an attempt to overthrow the Emperor of Mankind.

The Shadow Crusade laid waste to 26 worlds until Guilliman's retribution fleet finally caught up to the Traitors upon Angron's homeworld of Nuceria, which the World Eaters Legion was preoccupied with wiping clean of all life in vengeance for the treatment the Nucerians had merited out a century before to Angron.

The XIII Legion warship Courage Above All, Guilliman's temporary flagship, broke Warp at the system's edge, at the head of a large void armada consisting of 41 vessels.

The Ultramarines armada looked wounded, cobbled together from separate fleets. It was not a dedicated interdiction warfleet, but clearly a ragtag strike force, a lance thrust to the enemy's heart. Guilliman himself had done the best he could with limited resources.

The XIII Legion's cruisers and battleships ran abeam of the enemy fleet for repeated exchange of broadsides, offering targets too big and powerful to ignore, while the rest of the Ultramarines fleet used calculated Lance strikes from safer range. The armada then divided its assault potential, doing its utmost to destroy Lorgar's flagship Fidelitas Lex, and attempted to take the World Eaters' flagship Conqueror in a boarding action.

But the Ultramarines' warships not only fought a void war, they also attempted to take the fight to the surface of Nuceria, for this attack was personal. The Ultramarines had come for revenge against Lorgar and the Word Bearers, just as they had pursued Kor Phaeron all the way to the Maelstrom on the other side of Ultramar.

Several Ultramarines warships attempted to make a run on Nuceria, haemorrhaging Drop Pods, landers and gunships, forcing planetfall by any means necessary. The Ultramarines fleet swept over and against the Traitors like an insect horde.

But the tenacious commander of the Conqueror, Lotara Sarrin, put up a difficult fight and destroyed a number of Ultramarines vessels that attempted to make a run for the surface. Though the World Eaters' flagship transformed a number of the smaller vessels into flaming wreckage, the Ultramarines eventually punched through her tenacious defence and managed to land troops on the surface of Nuceria.

Meanwhile, the Fidelitas Lex was already a ruin, its armour pitted and cracked, its shields a memory. The cathedrals and spinal fortresses barnacling along its back were gone, laid waste by the Ultramarines' incendiary rage. The XIII Legion's armada attacked in strafing runs and protracted exchanges of broadsides, trading fire with the superior warship and accepting their own casualties as the cost of bleeding the bigger vessel dry.

Each assault left the Lex weaker, firing fewer turrets and cannons, taking punishment on its increasingly fragile armour. But she fought on. Crawling with smaller ships, the Lex lashed back with its remaining Macro-cannons, rolling in the light of its own burning hull. Guilliman guided the battle from the command deck of Courage Above All, and had decided that the Lex would die first, killed in the death of a thousand cuts and swept from the game board, while the Conqueror would be boarded and killed from within.

In the course of the battle in Nucerian orbit, the Conqueror could not rise to its sister-ship's defence. Both Traitor Legion flagships fought alone, starved of support and suffering the endless attacks of the XIII Legion's ragged armada. Salvation pods streamed from the Lex' sides and underbelly, along with heavier Mechanicum craft and bulk landers.

With the Legionaries of the Word Bearers already on the surface, the ship's human population fled in the vessel's final minutes. And still the great vessel fought -- rolling, turning, raging. The Ultramarines cruisers that drifted past burned as badly as the warship they were killing.

This void battle was a form of dirty fighting between warships, too close for the neat calculations of ranged battery fire. Instead, it was an up close and personal slugfest.

The Ultramarines Battle Barge Armsman intercepted the Conqueror and came abeam, launching assault carriers and boarding torpedoes. While the World Eaters flagship was busy repelling boarders, a number of smaller XIII Legion vessels slipped past her defences and launched Drop Pods, gunships and troop carriers.

The first Drop Pods hammered home on the planet's surface. Sealed doors unlocked and the first Ultramarines poured forth, bolters raised, moving in perfect and well-trained unity. But the World Eaters were waiting for them.

Those not lost to the Butcher's Nails at once had the presence of mind to note that these Ultramarines were not the pristine cobalt-blue warriors they had previously faced on the War World of Armatura. These Legionaries of the XIIIth wore cracked power armour, still scarred and burnwashed from some horrendous battle solar weeks or months before.

These were hardened veterans of the Calth Atrocity. They burned with a cold intensity to carry out the vengeance in their hearts, and were intent on getting to grips with the Word Bearers.

As was their way, the Ultramarines established footholds at defensible positions, clearing room for their reinforcements to land. For every position they held, another was overrun by the World Eaters in a storm of roaring axes, or lost to the Word Bearers' chanting, implacable advance. The XII Legion crashed against the XIII in rabid packs, showing why Imperial forces had feared to fight alongside them for many decades.

Uncontrolled, unbound, unrestrained, they butchered their way through Ultramarines strongpoints, enslaved to the joy of battle because of the Butcher's Nails cortical implants sandwiched within the meat of their minds. The XVII Legion also met their Loyalist cousins, replacing ferocity with spite and hate.

The Ultramarines returned it in kind, hungry for vengeance against the vile Traitors who had defiled Calth and damaged its star. Word Bearers units marched, droning black hymns and chanting sermons from the Book of Lorgar, bearing corpse-strewn icons of befouled metal and bleached bones above their regiments.

As the fighting raged, the burning shell of the Fidelitas Lex cut through the clouds into the planet's atmosphere, shuddering on its way east, rolling ever downwards, achingly slow for something of such scale. The weight of the Lex' massive plasma engines dragged the stern down first, colliding with the Nucerian ocean's surface far from shore.

In the meantime, the demigod in gold and blue had finally found the object of his obsession amidst the clamour of war. Guilliman confronted Lorgar, possessing the advantage of two weapons, but Lorgar's Crozius gave him a reach his brother lacked.

When they first met, there was no furious trading of frantic blows, nor were there any melodramatic speeches of vengeance avowed. The two primarchs came together once, Power Fist against War Maul, and backed away from the resulting flare of repelling energy fields.

Their warriors killed each other around them both, and neither primarch spared their sons a glance. Lorgar flicked the clinging lightning from the head of his Crozius, shaking his head in slow denial.

Both primarchs fought without heeding their warriors, their godlike movements an inconceivable blur to the Space Marines fighting around them. None had ever imagined the heroes of this new age would take the field against each other, nor could they have predicted the wellsprings of spite between them.

Guilliman confronted Lorgar for what his Legion had done across the Five Hundred Worlds of Ultramar. In his righteous anger the Ultramarines primarch struck Lorgar with one of his fists, battering the Word Bearers primarch's sternum. Lorgar repulsed him with a projected burst of telekinesis, weak and wavering, but enough to send his brother staggering.

The Crozius followed, its power field trailing lightning as Lorgar hammered it into the side of Guilliman's head with the force of a cannonball. Both primarchs faced each other beneath the grey sky, one bleeding internally, the other with half of his face lost to blood sheeting from a fractured skull.

As the two primarchs were locked in their furious life-and-death struggle, they were oblivious to the destruction being wrought around them. Suddenly, Angron burst forth from the Ultramarines ranks, his armour a shattered wreck, and both of his chainswords spat gobbets of ceramite armour plating and scarlet gore. Angron was plastered with the blood of the slain after hours in the crush of the front lines of intense combat.

On his chest hung a bandolier of skulls taken from the mass grave at Desh'elika Ridge. Blood painted them as surely as it marked Angron. Even through the constant pain generated by the Butcher's Nails, that simple fact pleased him. He wanted his deceased brothers and sisters to taste blood once more. He had carried them with him across Nuceria, letting their empty eyes witness the razing of his former, hated homeworld.

The World Eater primarch launched himself at Guilliman with murderous hatred. The two primarchs fell into a seamless, roaring duel where Lorgar and Guilliman had abandoned theirs. Guilliman was forced back by the storm of Angron's blows.

Roboute Guilliman & Angron

Roboute Guilliman fights viciously against his brother Angron upon Nuceria.

As the two primarchs fought, Guilliman landed a glancing strike, his fist pounding across Angron's breastplate. One of the skulls of Angron's fallen kinsman that hung from the chain worn across his breastplate was partially shattered and scattered across the ground.

Guilliman stepped back, his boot crushing the skull's remnants to powder. Angron saw it, and threw himself at his brother, his howl of wrath defying mortal origins, impossibly ripe in its anguish. Lorgar saw it, too.

The moment Guilliman's boot broke the skull, he felt the Warp boil behind the veil. The Bearer of the Word started chanting in a language never before spoken by any living being, his words in faultless harmony with Angron's cry of torment.

Lorgar enacted his dark plan to save his brother's life from eventual consumption by the Butcher's Nails, summoning the Ruinstorm to the world of Nuceria, tearing the sky open and unleashing a crimson torrent, formed from the ghosts of a hundred murdered worlds, raining blood.

Guilliman had been holding his own against both Traitor primarchs, until Lorgar ceased his attack and started his achingly resonant chant. Angron and Roboute still fought, with the lord of the Ultramarines giving ground each time Angron landed a blow. Angron plunged his chainsword up under Guilliman's breastplate -- a shallow stab, but a telling one. The Ultramarines primarch crushed the impaling sword in one fist and staggered back, truly bleeding now.

Despite the maelstrom of combat and sorcery raging around them, Angron still fought Guilliman, standing above the kneeling Ultramarine primarch. He had not even noticed the storm of blood streaming from the sky in a red torrent. Sparks sprayed from Roboute's raised gauntlets as he struggled to ward off blow after blow. He was beaten and down. His wounds bled profusely, a palette of proud defeat.

His warriors fought desperately to retrieve him. Fortunately they were granted a brief reprieve, as Lorgar's incantation locked up Angron's muscles, and began to transform the Red Angel into a new form as a Daemon Prince of Khorne. Guilliman took the opportunity to escape into his sons' defiant phalanxes, retreating in enviable unity.

Lorgar saw the expression of disgusted awe on his brother's face as the wounded Ultramarine primarch stared at Angron's metamorphosis atop the mound of dead sons from all three bloodlines of Space Marines. The XIII Legion continued to fire even in retreat, leaving the world of Nuceria battered and bloody. Their campaign against the two Traitor Legions was over...for now.

Roboute Guilliman escaped from Nuceria, unable to face or even fully comprehend what both of his brothers had become through their corruption by the Ruinous Powers.

The World Eaters completed their purge of Nuceria until not one human life remained on the benighted world. Angron, now the very embodiment of the Blood God's Eight-Fold Path, shook the dust of the world from his feet and did not think of it again.

Imperium Secundus

As a result of being cut off from access to Terra and much of the rest of the galaxy by the vast Warp Storm called the Ruinstorm that was created by the treacherous Word Bearers at the Battle of Calth, Guilliman feared that the great dream of Human unity was in danger.

With no way of knowing whether Terra was under assault or the Emperor was even still alive, Guilliman moved to safeguard the ideals of the Great Crusade and the Emperor by creating a second Human interstellar empire, the Imperium Secundus, as a contingency. It was an action he would later consider one of his greatest blunders.

Many Loyalist Space Marines trapped behind the line of the Ruinstorm were brought to Macragge thanks to the activation of the ancient xenos device located on the Ultramarran world of Sotha known as the Pharos, which functioned much like the now-obscured Astronomican as a beacon in the Warp.

Guided by the Pharos' beacon, many Loyalist warships of the Shattered Legions and other Loyalist forces were able to make their way through the Immaterium to the Ultramarines' homeworld.

Not wanting to appear vain and power-hungry like his brother Horus, Guilliman refused to declare himself the Emperor of Imperium Secundus, instead initially trying to convince his fellow Primarch Lion El'Jonson, who had arrived at Macragge with his Dark Angels Legion, to take the position despite being distrustful of El'Jonson's motives.

While organising the creation of Imperium Secundus, Guilliman survived an assassination attempt by an Alpha Legion squad disguised as Aeonid Thiel and other Ultramarines. Later, when the Night Lords Primarch Konrad Curze, who had secretly taken refuge on the Dark Angels' flagship was let loose upon Macragge, Guilliman and the Lion battled the Night Lords primarch together but were led into a trap by the Night Haunter.

Instead of being cornered, Curze detonated charges and brought the entire structure into which the other primarchs had been lured down upon their heads. Guilliman and the Lion survived thanks only to the Loyalist Iron Warrior Barabas Dantioch activating the Pharos, which teleported the pair to Sotha.

El'Jonson and Guilliman then made their way back to Macragge, where the Blood Angels Legion had recently arrived in the wake of the horrors of the Signus Campaign. Guilliman decided to name the reluctant Sanguinius the Regent of Imperium Secundus, so none would hold the title of "Emperor."

However, in the short history of the existence of Imperium Secundus, Guilliman frequently clashed with his distrustful and taciturn brother Lion El'Jonson over policy. Obsessed with hunting for Konrad Curze on Macragge, the Lion insisted that the Night Haunter was behind the rebellions which began to plague the Ultramarine homeworld and he demanded that martial law be instituted, which Guilliman strongly resisted.

After a suicide bombing struck an Astartes convoy on Macragge, the Dark Angels were deployed by the Lion to establish martial law without Guilliman's express permission.

Guilliman and El'Jonson again disagreed over the rebellion that had broke out in the Illyrium region of Macragge, with the Dark Angels primarch wishing to unleash weapons of mass destruction in an attempt to flush the rebels out as he suspected Curze was hiding in the region.

When Guilliman again objected to such an indicriminate use of force that would take much innocent life, the Lion instead commanded a more conventional Space Marine assault on Illyrium, and Curze was finally captured. Again at Guilliman's insistence, the Night Haunter was given a public trial to account for his treason.

During the trial, Curze revealed that Lion El'Jonson had ordered secret orbital strikes against the Illyrian rebellion in express contravention of Guilliman's wishes. This revelation enraged the Dark Angels primarch and nearly led him to kill Curze in the midst of the trial.

Angered by their brother's duplicity and consistent disregard for Imperial principles, Guilliman and Sanguinius dismissed and ordered El'Jonson and the Dark Angels to leave Imperium Secundus, but repenting of his actions, the Lion later requested that he become Curze's jailer instead, as the Night Haunter's life had been spared.

Second Battle of Davin

Following the Trial of Konrad Curze, Sanguinius, Lion El'Jonson, and Guilliman all agreed that the Imperium Secundus had been a mistake and should be disbanded. Instead, they agreed to try and breach the Ruinstorm to reach Terra and aid the Emperor, who they had learned still lived, in the defence of Terra from Horus.

As they sought to navigate the Ruinstorm, the combined Loyalist fleet of Ultramarines, Dark Angels and Blood Angels came across a variety of horrors and word of an entity spreading destruction across the galaxy known as the "Pilgrim." During the voyage through the Ruinstorm, Guilliman's fleet was ambushed by Traitor forces at Anuari, where Guilliman survived an assassination attempt by the Word Bearers armed with the Chaos blades known as Athames.

Believing he could study the weapons to gain a better understanding of Chaos and potentially use such knowledge against the Traitors, Guilliman kept the blades in his vault.

During the Battle of Pyrrhan, Guilliman commanded the Ultramarines personally while Sanguinius received a vision and realised that the fleet needed to go where the Horus Heresy had truly first begun, the cursed world of Davin. Reluctantly, Guilliman and Lion El'Jonson agreed to trust in Sanguinius despite their skepticism of his vision, but both had thought they would simply destroy the world upon arriving.

After arriving in orbit of Davin, Sanguinius shocked El'Jonson by boarding the Dark Angels flagship Invincible Reason and taking the captive Konrad Curze with him. Sanguinius hoped to use Curze's known psychic precognitive abilities to determine what he was meant to do upon Davin. Sanguinius commanded a mass landing on the world, and the enraged El'Jonson nearly ordered that Davin be subjected to Exterminatus regardless of Sanguinius' presence on it.

Brought back to his senses before such a horrific betryal could occur, a chastened El'Jonson explained to Guilliman that he believed something was trying to manipulate them begin walking the path of damnation like Horus and the other Traitor primarchs. Convinced that his brother was correct, the Ultramarine primarch realised the source of the corruption. Guilliman retreated to his vault, and crushed the captured Athames with his Power Fist even as he declared to the Dark Gods that he would not be tempted as Horus had.

On Davin, Sanguinius was trapped within a Warp portal and did battle with the daemon Madail while Guilliman and El'Jonson desperately tried to reach him. A vicious battle erupted both on Davin and above it, in which Guilliman's acting flagship Samothrace was destroyed by the Daemonship Veritas Ferrum.

During the battle that erupted at Davin's Temple of the Serpent Lodge, the place where Horus had been corrupted by Chaos, Guilliman and El'Jonson finally managed to put aside their lingering emnity and fight together as brothers should, defeating a massive Soul Grinder.

Eventually, Sanguinius was able to escape from the Warp and the Space Marine forces evacuated the world to orbit. Davin was destroyed by Cyclonic Torpedoes, and with its anchor in realspace gone, the daemonic fleet which had protected the world vanished.

Left behind in the space where Davin had been a breach in the Ruinstorm became visible to the combined fleet. The path through led to Terra, but upon further study it became apparent that somehow Horus had foreseen that this route to the Throneworld would open and he had left behind a massive fleet of Traitor warships to prevent the passage of the Loyalist fleet through that route.

Guilliman and El'Jonson agreed tthat the Ultramarines and Dark Angels fleets would face the Traitors while Sanguinius and the Blood Angels slipped through the breach in the Ruinstorm and made directly for Terra, for that was their destiny as predicted by Sanguinius' visions of the future. If the Blood Angels did not make it to the Throneworld, the Traitors would claim final victory.

The plan proved successful, and in the solar months that followed, the Ruinstorm began to dissipate, allowing easier travel through the Warp. Guilliman gathered whatever Ultramarine forces he could and at last began to make his way to Terra.

In his path lay a large defensive chain of hundreds of worlds manned by the Iron Warriors. In a series of bitter engagements, both sides took heavy losses but the Ultramarines were able to maintain a slow and painful advance on the Throneworld.

Ultimately, Guilliman was able to set a final course for Terra. Travelling at maximum speed, his Legion was only solar hours away when the final battle of the Siege of Terra began aboard the Warmaster Horus' flagship Vengeful Spirit.

Siege of Terra

Thanks to the Ruinstorm and the Traitors' delaying actions at the Battle of Calth, during the Shadow Crusade at the Second Battle of Davin and in the months afterwards, there was little that Roboute Guilliman could do in support of his Emperor during the crucial Siege of Terra.

As the long and bloody years of the Horus Heresy passed after the Drop Site Massacre, the Traitor Legions under the command of the Warmaster Horus finally closed on the homeworld of Mankind. They launched their great assault against the Imperial Palace while they believed a good portion of the Loyalist Space Marine Legions remained occupied in other regions of the galaxy.

While the forces of Chaos came close to battering down the gates of the Palace, the Loyalists' stout defence managed to hold the line long enough for Loyalist reinforcements to drop from the Warp on the edges of the Sol System. Salvation was coming.

In orbit of Terra, Horus' allies delivered the fateful news to the Warmaster while he sat directing the battle for the Imperial Palace. The Ultramarines, Dark Angels and Space Wolves Legions were only solar hours away from reinforcing the Emperor and His Loyalist defenders. Horus knew that his gamble had failed.

What happened next is disputed by Imperial scholars. Some believe Horus disabled his flagship's shields because he experienced one last moment of regret for his great betrayal, while some believe it was a personal challenge to the Emperor so that Horus could face him even without battering down the gates of the Imperial Palace.

Nevertheless, Horus lowered the shields of his flagship -- the Battle Barge Vengeful Spirit -- allowing the Emperor, the Blood Angels' Primarch Sanguinius and a company of Imperial Fists to teleport aboard and ultimately slay him, ending the Horus Heresy.

The Emperor was mortally wounded in the exchange and interred in the Golden Throne immediately afterwards by the Primarch Rogal Dorn, leaving a dangerous void of political power and authority in the Imperium.

The Ultramarines did not arrive until after Horus' defeat, and they found Terra and the Imperium in ruins. Guilliman steadfastly refused to allow the Imperium to fall, and began dispatching elements of his Legion to all corners of the galaxy to stem the tide of invasion and unrest as the other Loyalist forces recovered and rearmed.

Imperial Reform

The Loyalist Space Marine Legions had lost tens of thousands of troops during the fighting of the Heresy, and half of the original 18 Legions had sided with Horus and been corrupted by Chaos. As a result, the number of Astartes left to the Imperium after the end of the Heresy was very few, yet never were they more needed.

The confusion and disorder following the Horus Heresy had left the Imperium weak and vulnerable. Everywhere the enemies of Humanity prepared to attack. Many worlds remained in the grip of Chaos.

Into this breach stepped Roboute Guilliman and the Ultramarines. Always the largest of the Astartes Legions since the middle years of the Great Crusade, the Ultramarines found themselves divided and dispatched all over the Imperium in a desperate effort to stem the tide of invasion and unrest.

Guilliman, ever the statesman, took over control of the Council of Terra, establishing the position and authority of the Lord Commander of the Imperium. In this role, he guided the Imperium forward after the internment of the Emperor in the Golden Throne for over a Terran century, through the long hard days of the Great Scouring when the Imperium reclaimed and cleansed the worlds lost to the Traitors and reestablished Imperial rule across the galaxy.

The Ultramarines successfully held the Imperium together during a time of intense danger. Macragge was able to supply new recruits at such a rate that before long the Ultramarines alone accounted for more than half the total number of Space Marines, and few were the star systems where their heroism went unnoticed. Within decades, order was restored to the Imperium.

After decades of intense fighting, stability was restored. To prevent a single commander having as many superhuman Astartes at his command as Horus had, Guilliman reformulated the sizes of all of the Loyalist Space Marine Legions into thousand-man Chapters, breaking apart the 9 original Loyalist First Founding Legions into the much smaller Second Founding Chapters.

Never again would one person, no matter how noble and unblemished their motives, wield the power of an entire Space Marine Legion. At the same time, Guilliman had been hard at work for decades on a new method for waging war that finally reached its fruition after the Horus Heresy.

The rationale and proper organisation of Space Marine Chapters are the main topic in this masterwork of military strategy, the Codex Astartes.

Its doctrines would reshape the future of all Space Marines and forevermore dictate the foundation for the Imperium's military strength and the ultimate survival of Mankind.

The Second Founding of the Space Marines was decreed seven Terran years after the death of Horus and the end of his Heresy. Most of the old Loyalist Legions divided into fewer than 5 Successor Chapters, but the Ultramarines were divided many times.

The exact number of Successor Chapters created from the Ultramarines is uncertain: the number listed in the oldest copy of the Codex Astartes gives the total as 23, but does not name them. With the Second Founding, the size of the Ultramarines force was much reduced. Most of the Space Marines left Macragge to establish new Chapters elsewhere.

The Ultramarines' fortress-monastery on Macragge, the Fortress of Hera, had been built to accommodate more than ten times as many Space Marines as now remained on their homeworld. As a result, its arsenals and weapon shops were partially dismantled and taken by the new Chapters to found their own bases. The genetic banks of the Ultramarines, and the huge recruitment organisation, were similarly reduced.

As a result of the Second Founding, the Ultramarines' gene-seed became pre-eminent across the Imperium. The new Chapters created from the Ultramarines during the Second Founding are often referred to as the "Primogenitors," or "first-born." The lasting heritage of Guilliman was not only genetic, but spiritual.

Even to this day, 10,000 standard years later, all the Primogenitor Chapters venerate Roboute Guilliman as their own founding father and patron, and hold the ruler of Ultramar, whoever he be, as the exemplar of all that it means to be a Space Marine. So did the Ultramarines rise to become preeminent amongst their brother Chapters.

Death of the Avenging Son

Roboute Guilliman continued to serve with the Ultramarines Chapter, leading them and the Imperium as its Lord Commander for a hundred standard years after the Second Founding. It was said that during those years, Guilliman led several incursions alongside his brother primarchs against the remaining Chaos Space Marines.

During one such conflict on the world of Eskrador, Guilliman faced his former brother Primarch Alpharius of the Alpha Legion. Due to the vanity of Alpharius, Guilliman utilised a surprise attack which struck at the heart of the Alpha Legion forces and managed to kill Alpharius in a duel.

However, Guilliman and the Ultramarines were greatly mistaken in their belief that the snake would die without its head, as indeed, the Alpha Legion's symbol is a hydra, the multi-headed serpent. The Alpha Legion retained its coherency as a fighting force and managed to drive the Ultramarines back in repeated assaults, undaunted at the loss of their primarch.

Guilliman eventually was forced to pull his warriors back into orbit and bombard Eskrador from above, but the Alpha Legion would remain a stubborn and insidious threat to the Imperium for millennia to come.

It was in this period, at an unknown point, that Guilliman first struck up a relationship with the Archmagos Dominus Belisarius Cawl. Guilliman charged Cawl with two important tasks for the future -- developing a technological means to resurrect him from death should he fall and the development of the Primaris Space Marines, a new generation of transhuman warriors that could improve upon the Emperor's original design and learn from the failures of the Horus Heresy. Cawl would spend the next 10,000 years in pursuit of both charges.

Guilliman met his seemingly final fate during the Battle of Thessala in 121.M31, when he was laid low by the Traitor Daemon Primarch Fulgrim of the Emperor's Children, who had become a Daemon Prince of Slaanesh.

During this encounter with his former brother, Fulgrim managed to fatally injure Guilliman in the neck with his poisonous blade (which was remarkably similar to the Anathame sword that was used by Dark Apostle Erebus to fatally wound Horus on Davin's moon).

Temple of Correction

The Temple of Correction within the Fortress of Hera on Macragge.

Fatally poisoned by his one-time brother, Roboute was transported back to Macragge in a stasis field, and has remained entombed in the field for 10,000 years, frozen in time. Although physically impossible within the null-time of a stasis field, it was believed by many pilgrims to his shrine that his wounds were healing, and that one day he would awaken again when the Imperium needed him most.

The Shrine of Guilliman built to contain his body was one of the most holy places in the entire Imperium, and one which welcomed millions of pilgrims every year. It lay within the Temple of Correction, a vaulted sepulchre forming a small part of the Ultramarines' vast northern polar fortress on Macragge.

The temple was a miracle of construction and typical of the attention to detail to which the Ultramarines apply themselves. Its proportions defied the human mind by the scope and grandeur of its design. The multi-coloured glass dome that formed the roof was the largest of its kind.

Even the Techno-magi of the Adeptus Mechanicus came to marvel at the structure said to have been designed by Roboute Guilliman himself. According to the Ultramarines there was enough marble within the temple to build a mountain, and sufficient adamantium and shining plasteel to construct a sizable Imperial warfleet.

Within this edifice was the great marble throne of Roboute Guilliman, and upon that throne sat a regal corpse. Though the best part of 10,000 years had passed since his death, the primarch's body was perfectly preserved. Even his death wounds from Fulgrim's blade were visible upon his throat.

His mortal remains were preserved from the ravages of time by means of a stasis field that isolated the primarch from the time-stream of normal four-dimensional space-time. Everything encompassed by the field was trapped in time and could neither change nor decay. There were some in these years, however, who claimed the primarch's wounds did change. They said that Guilliman's body was slowly recovering and that his wounds showed mysterious signs of healing.

Others denied the phenomena, and pointed out the sheer scientific impossibility of change within the stasis field. Yet enough believed the stories to come and witness for themselves the miracle of the primarch, generation after generation.

13th Black Crusade

For 10,000 standard years the Emperor of Mankind has sat immobile on the Golden Throne of Terra, His withered body little more than a husk of the great man that He once was. His grand vision, the Imperium of Man, endures -- yet it does not prosper, for it lingers under a pall of misery and persecution, suspicion and mistrust. It is assailed on all sides and from within by Heretics, witches and aliens, and only by the endless sacrifice of countless citizens does the Imperium continue to exist.

Yet now, at the close of the 41st Millennium, the people of the Imperium face their greatest trial. Orks wreak havoc across the galaxy, the T'au Empire expands in the Eastern Fringe, the Tyranids send vast alien swarms from beyond the stars to consume all in their path, and the Necrons awaken to reclaim what was once theirs. And above all, more deadly than any other foe, the forces of Chaos chose this moment to begin their most concerted invasion of the Imperium.

Under the eye of Abaddon the Despoiler and his 13th Black Crusade, countless worlds fell to darkness. Madness and heresy are rife and violent Warp Storms tear great rents in the galaxy. Blind in their ignorance, the High Lords of Terra send billions to their deaths in a bid to save the Imperium.

Yet it took the Aeldari, a more far-sighted race, to realise that what the Imperium needed now was a hero, a symbol of the Emperor's will made manifest. The Imperium needed a primarch.

The War for Cadia

Led by the Living Saint, Saint Celestine, the Cadian Shock Trooper regiments of the Imperial Guard defend Kasr Kraf on the Fortress World of Cadia from the forces of Chaos.

The full might of the 13th Black Crusade assailed the Fortress World of Cadia, which stood as the lone sentinel of the Cadian Gate, the only predictably stable way out of the Warp maelstrom known as the Eye of Terror. Though severely outnumbered and assailed on all sides, the Imperial defenders held their ground, mounting a valiant defence under the superlative leadership of the Lord Castellan of Cadia, Ursarkar E. Creed.

As the conflict became increasingly desperate, many heroes of the Imperium gathered on Cadia. Space Marines from multiple Chapters lent their strength to the defence, including the Black Templars of Marshal Marius Amalrich, and the Imperial Fists of Captain Tor Garadon, who brought the Star Fort Phalanx into the war.

Saint Celestine swept down upon Cadia in its darkest hour, her miracles instilling faith in its ragged protectors. Inquisitor Katarinya Greyfax, long a prisoner of the Necron Lord Trazyn the Infinite, was released from captivity to lend her prodigious will and talents to the cause.

Yet the key to victory upon Cadia was discovered by the ancient Martian Tech-priest, Archmagos Dominus Belisarius Cawl of the Adeptus Mechanicus. Urged on by the Harlequin Shadowseer Sylandri Veilwalker, he had unlocked the secrets of the Necron-built black pylons that studded the surface of Cadia and other worlds throughout the Cadia System.

Abaddon had long sought out these ancient and mysterious structures to destroy them during his many Black Crusades, which weakened the veil between reality and the Immaterium. In truth, Cawl had been en route to honour an ancient pact made with the Lord of Ultramar many Terran millennia ago, but on Cadia he saw a chance to reverse the Despoiler's work and perhaps close the Eye of Terror forever. But it was not to be.

Cadia's Death

The Fortress World of Cadia tears itself apart

Though the servants of the Emperor fought with dogged determination and courage, Cawl's works were undone when the pylons were destroyed and Cadia was dealt a final death blow. Those few Imperial defenders that were left alive were forced to flee before the flood of the forces of Chaos that assailed the doomed world. As they did so a terrible Warp rift yawned in their wake as the Eye of Terror actually began to expand.

Yet there was still one chance of salvation that remained -- Cawl's ancient pact and the mysterious artefact that he transported within an armoured auto-reliquary. Declaring themselves the Celestinian Crusade in honour of the Living Saint who still lit their way through the darkness, the surviving warriors of the Imperium made for the Macragge System within the Realm of Ultrmar, with the forces of the Despoiler hot on their heels.

Emperor's Salvation

With the aid of Yvraine, the surviving Imperials of the 13th Black Crusade retreat to the Webway gate on the ice moon of Klaysius in the Cadia System.

At the same time, the Aeldari race had been rocked to its very foundation by a cosmic upheaval of great significance. Ynnead, the Aeldari god of the dead, had partially awoken in the æther and chosen a former Aeldari of Craftworld Biel-Tan to be his prophet.

Yvraine, the Daughter of Shades, had walked many Paths during her long life, from that of dancer to Warlock to Aspect Warrior. She eventually had become a famed Corsair leader until a mutiny forced her to flee into the Webway, where she ended up in the Dark City of Commorragh, the primary home of the Drukhari.

Fighting as a gladiatrix in the dark city's infamous Crucibael arena, she defeated many foes before having fallen to a priestess of Morai-Heg, however, while she lay between life and death, she was resurrected by Ynnead and chosen to act his prophet in the material realm. Her rebirth during this Night of Revelations caused a great Dysjunction within Commorragh, and the Dark City was beset by the daemonic servants of Slaanesh.

Fleeing the Drukhari forces of the Dark City's Supreme Overlord, Asdrubael Vect, Yvraine, aided by the mysterious warrior known as the Visarch, and followed by some of the Drukhari who believed in her cause, successfully brought word of the Whispering God's awakening to Craftworld Biel-Tan. While there, the craftworld underwent a swift and terrible cycle of death and rebirth during the Battle of Biel-Tan that brought the Yncarne, avatar of Ynnead, into being.

Yvraine High Priestess

Yvraine, Daughter of Shades, summons the Yncarne, the Avatar of Ynnead, Eldar God of the Dead, into being upon Craftworld Biel-Tan

Some amongst the Asuryani embraced Yvraine's belief that the cycle of death and rebirth would be their salvation, and became her followers, known as the Ynnari -- the Reborn.

Others rejected this upstart's teachings as arrogance and dangerous in the extreme. But Yvraine pressed on regardless, and departed Biel-Tan in search of the time-lost artefacts known as the Croneswords and formulated a desperate plan to turn back the tides of Chaos.

It was this mission that brought Yvraine through the Webway to the frozen moon of Klaisus in orbit of the Fortress World of Kasr Holn in the Cadia System, leading an army of the Eldar from every faction who once more laid claim to the ancient name of Aeldari.

They emerged from the moon's Webway gate just in time to rescue the Celestinian Crusade from their pursuers. Driving off the Heretic Astartes of the Black Legion, the Ynnari negotiated common cause with the Celestinians, agreeing to aid them in reaching the Realm of Ultramar.

Thus, as Warp Storms billowed and spread across the galaxy, the assembled pilgrims hastened through the Webway, bearing a thin sliver of hope between them.

Ultramar Campaign

"They shall be my sons, and in them will live the hopes of a unified humanity. Theirs will be the strength to prevail, not only when victory lies within easy reach, but even when it seems unattainable, when doom settles like a shroud all about. In those times of darkness, my noble sons will shine the brightest of all."

—Attributed to the Emperor of Mankind
Realms of Ultramar 2

A Departmento Cartographicae Map of the Realm of Ultramar at the time of the 13th Black Crusade in 999.M41

In the closing years of the 41st Millennium, the stellar realm of Ultramar came under sustained attack from myriad foes. Menacing shapes stirred in the intergalactic void, the Tyranids of Hive Fleet Leviathan drifting inexorably towards Guilliman's realm.

The Arch-Arsonist of Charadon, one of the greatest Ork Warlords in the galaxy, led a monstrous WAAAGH! from his anarchic domain with the intent of overrunning the Ultramarines' eastern defences. Yet the greatest threat of them all was that posed by the dark servants of Chaos.

A vast horde of Traitors, Renegades, mutants and madmen fell upon Ultramar under the leadership of the foul Daemon Prince M'kar the Reborn. That invasion plunged dozens of worlds into bloody battle, war raging from the worlds of Espandor and Tarentus to oceanic Talassar. Yet eventually, after long solar months of sorrow, bloodshed and loss, the Ultramarines prevailed. M'kar was defeated and his armies driven off, pursued to the stellar void beyond the bounds of Ultramar.

So began a period of rebuilding and consolidation across Ultramar, as Marneus Calgar and his Chapter led their peoples' efforts to shore up the battered defences of their realm. It was a period of repose and recovery that was to be all too swiftly ended.

In the days immediately after the fall of Cadia at the climax of the 13th Black Crusade, Abaddon the Despoiler, Lord of the Black Legion, was informed by the Chaos Sorcerer Zaraphiston of a disturbing reality. The sorcerer had discovered through his Warp-scryings that the Archmagos Dominus Belisarius Cawl had escaped Cadia's destruction with a device in his possession that could turn the tide of the Long War in favour of the Imperium of Man.

The Despoiler also learned that Cawl was one of a number of survivors of Cadia, now calling themselves the Celestinian Crusade, who had escaped into the Webway with the aid of the Aeldari Ynnari and were making their way to Macragge, the homeworld of the Ultramarines Chapter.

To neutralise the nascent threat to his coming triumph over the Corpse-Emperor, the Despoiler detached a portion of his Black Fleet and ordered a Chaos Space Marine invasion of the Realm of Ultramar as part of the 13th Black Crusade.

So it was that Abaddon was able to muster a sizable force of warriors from the Black Legion, the Iron Warriors, the Night Lords and a number of other Traitor factions, and hurl them against the worlds of Ultramar.

While some Heretic Astartes warbands struck at the outer star systems in an effort to tie up potential Loyalist reinforcements, the main Traitor horde rode the tempestuous currents of the Warp straight into the Macragge System itself. So began another desperate and bloody invasion of the Ultramarines' realm remembered as the Ultramar Campaign of the 13th Black Crusade.

The Celestinian Crusade, named for Saint Celestine, the Living Saint who had come to aid the defenders of Cadia in their darkest hour, was led not only by its namesake but also by Archmagos Cawl, Marshal Marius Amalrich of the Black Templars, and Inquisitor Katarinya Greyfax of the Ordo Hereticus. These individuals, joined by the Ynnari's commanders Yvraine, the Daughter of Shades, and her war leader The Visarch, first stepped from the Webway and onto the soil of the Shrine World of Laphis in the Macragge System.

They were surprised to discover that they had set foot in a war zone, but they soon defeated the local Chaos forces that had been in the vicinity of the Webway portal. The Celestinians and their uneasy Aeldari allies defeated the Heldrakes besieging the local Ultramarines fortress and then convinced the Space Marines to grant them passage to Macragge, though Yvraine and the Visarch sent the majority of the Ynnari back into the Webway to carry out missions more pressing for their people.

The Celestinians arrived at Macragge aboard an Ultramarines Strike Cruiser to discover that the capital world of Ultramar had come under a full-scale invasion by the forces of Chaos. While a massive battle raged in orbit between the Chaos and Loyalist fleets, on the ground the Fortress of Hera, the Ultramarines' fortress-monastery, was in danger of falling to the Archenemy.

Gaining an audience with Marneus Calgar, the Chapter Master of the Ultramarines and the Lord of Macragge, Belisarius Cawl revealed that he was over 10,000 standard years old and had known the Ultramarines' Primarch Roboute Guilliman during the time of the Horus Heresy.

Cawl explained that he had been tasked by Guilliman with finding a way to restore the primarch to life even before his mortal wounding by the Daemon Primarch Fulgrim in the time after the Heresy. Within the auto-reliquary he had kept with him since before coming to Cadia, Cawl maintained a unique suit of Artificer Armour, the Armour of Fate, that could sustain the primarch's life functions, and the Emperor's Sword, a weapon in which was embedded a small portion of the Emperor's own psychic essence.

Though Calgar and his Chapter Council were wary of the Celestinians, especially because they had openly allied themselves with xenos, Chief Librarian Tigurius supported their story. He explained to Calgar that he had been having prophetic dreams and the arrival of the Celestinians was no coincidence.

In fact, it might be the Ultramarines' only hope in the face of the Chaos onslaught. Calgar accepted this explanation, and allowed the Celestinians and the Ynnari into the Temple of Correction where Guilliman sat in stasis despite his reservations about the newcomers.

While Cawl began his work on the time-frozen body of Guilliman, seated upon his throne in the temple, the Black Legion took notice of the activity and launched a massive assault upon the Temple of Corrections, fearful of what the Loyalists were attempting.

The Celestinians, aided by the Ultramarines' officers and the 3rd Brotherhood of the Grey Knights led by Grand Master Aldrik Voldus who had come to Macragge to aid the defence, faced off against over a hundred Black Legionaries.

Yet, even as the Loyalists fought to give Cawl just one more solar second to complete his work, more Chaos forces poured into the shrine from above using Dreadclaw assault boats, and the defenders quickly found themselves overwhelmed.


The resurrected Primarch Roboute Guilliman.

Only then, at the last, did Yvraine call upon the power of her patron, Ynnead, the partially awakened Aeldari god of the dead. The alien god's power over life and death combined with Cawl's arcane technology to heal the primarch's wound and awaken him from his ten-thousand-year slumber.

An awakened and enraged primarch proved more than the Chaos attackers were prepared to deal with. Guilliman shattered the attacking forces of Chaos and provided an extraordinary surge in morale for his Ultramarines and the other Loyalist forces.

The Imperials quickly swept the Black Legion before them, breaking the back of the Chaos assault upon the Ultramarines fortress-monastery. In that one moment of resurrection, the fate of Macragge and of all Ultramar was decided.

In the wake of the battle in the Temple of Correction, Guilliman was crowned as the restored primarch of the Ultramarines Chapter and all of its Successor Chapters, and as the Lord Macragge and rightful ruler of Ultramar. Marneus Calgar happily ceded the role of Chapter leadership to his gene-father, while Guilliman declared that the autonomy of all the worlds that had once belonged to the Realm of Ultramar and gone their separate ways in the millennia since the Horus Heresy was revoked.

Ultramar was to be restored to what it had been in the golden age of the Imperium, a miniature stellar empire comprising five hundred human-settled worlds. Once in full control of the Loyalist forces on Macragge, the primarch's strategic genius was unleashed, and the forces of Chaos were driven off of Macragge and then from most of Ultramar within approximately seven solar months.

At that time, Yvarine, the Visarch, and the remaining small force of Ynnari took their leave to pursue their own agenda, with the primarch's wary blessing -- and thanks.

During this time, the primarch found himself suffering from a spiritual malaise, as he was forced to come to grips with the reality of the Imperium of Man in the late 41st Millennium. Far from the golden rule of prosperity, scientific wonder and freedom promised by the Emperor, the Imperium in His absence had degenerated into a despotic, tyrannical regime defined by ignorance, fear and superstition.

At first despairing, Guilliman finally found hope for humanity's future once more deep in his heart and declared that he must make his way from Macragge through the roiling tides of the Warp to Terra. There he would consult with his father, the Emperor, and determine what must be done to save the Imperium from the servants of the Dark Gods.

And so began the fateful Terran Crusade.

Terran Crusade

Guilliman vs Magnus

Primarch Guilliman and his Terran Crusade forces are assaulted by Magnus the Red and his Thousand Sons in a voidship graveyard on Luna.

Gathering forces from all across the Imperium who were able to reach Macragge as the Warp grew ever more turbulent in the wake of the 13th Black Crusade, the primarch assembled a massive Imperial fleet to reach Terra, beginning what was later remembered as the Terran Crusade.

Leaving Macragge and Ultramar in the capable hands of Marneus Calgar, who was once more placed in overall command of the Ultramarines, Guilliman's crusade fleet was passing near the great Warp rift known as the Maelstrom when it was intercepted by a Chaos fleet led by the Daemon Primarch Magnus the Red and his Thousand Sons Traitor Legion.

Magnus had stirred himself from the Planet of the Sorcerers for the first time in millennia in recent days, to assault the Fenris System of his ancient foes the Space Wolves, and now to confront his former brother. The Thousand Sons primarch cast a potent sorcerous ritual that flung the Terran Crusade Fleet into the Maelstrom, with no apparent way for it to escape from the labyrinthine clutches of that wound in reality.

With time in the Warp indeterminate, the Terran Crusade wandered from Daemon World to Daemon World within the Warp rift, taking steady casualties from the constant daemonic assaults. All during this time Roboute Guilliman's guilt and frustration began to grow, weighing down his psyche as the Loyalists found it impossible to escape the Maelstrom's clutches.

But a beacon of hope came when on one such world Guilliman received a psychic message from the Asuryani Farseer Eldrad Ulthran, now an ally of the Ynnari, which laid out a series of landmarks for the Imperial fleet to follow to escape the Warp rift.

But when the much-diminished crusade reached the starship graveyard which marked the passage back to realspace, it was met by another massive Chaos fleet, this time of the piratical Chaos Space Marines known as the Red Corsairs, led by the Lord of Change Kairos Fateweaver.

The Chaos forces assaulted every voidship in the Imperial fleet, and Kairos ultimately succeeded in defeating Guilliman by using his psychic powers to wrap the primarch in chains literally crafted from his own guilt. Threatening the immobilised primarch's life, the Greater Daemon forced the rest of the Imperial fleet to surrender.

The Terran Crusade found itself in dire straits, brought by Fateweaver's command to a Blackstone Fortress hidden in the Maelstrom by the Red Corsairs, a secret gift from Abaddon the Despoiler. There the primarch and his remaining followers would have rotted for eternity were it not for intervention from an unexpected source -- the Aeldari Harlequins led by the Shadowseer Sylandri Veilwalker and Cypher, the mysterious Fallen Angel who was a sometimes enemy and sometimes ally of those loyal to the Emperor.

In return for a promise to bring the Fallen Angel before the Golden Throne, Cypher freed the primarch and his compatriots. With their starships lost to them, their crews sacrificed to the Ruinous Powers, Veilwalker offered another path to Terra -- through the Webway gate that lay at the heart of the massive xenos star fortress.

The Imperials forced their way deep into the interior of the Blackstone Fortress, defeating the sudden influx of Khornate and Tzeentchian daemons that barred their way. The last hurdle was represented by the Bloodthirster Skarbrand the Exiled One who directly assaulted the primarch after slaying the heroic Emperor's Champion Marius Amalrich.

Guilliman managed to defeat the Greater Daemon in hand-to-hand combat largely because of the wound that Amalrich's Black Sword had left in Skarbrand's fiery hide.

With Skarbrand's fall, the Terran Crusade passed through the Webway towards Terra, only to discover that the Labyrinth Dimension was already haunted by Magnus the Red and the forces of the Thousand Sons.

As Veilwalker explained that there had long existed a secret exit of the Webway on Luna, the moon of Terra, Guilliman realised that his daemon brother had been waiting for them.

As soon as they opened the Webway exit in the Sol System, the Thousand Sons would rush through behind them, unleashing a major Chaos invasion right on Terra's doorstep, allowing Magnus to gain the glory ahead of the Despoiler.

Guilliman Saviour

Roboute Guilliman, Primarch, Saviour of Humanity and Lord Commander of the Imperium, prepares to lead Mankind against the encroaching forces of Chaos.

But with aid from the Harlequins and other Imperial forces such as the Sisters of Silence and the Imperial Fists, Guilliman and his Terran Crusade survivors managed to overwhelm the Thousand Sons and cast Magnus back through the Webway portal, permanently sealing it so that it could never be used again to threaten the Throneworld of the Imperium.

At long last, Guilliman was escorted by the awed defenders of Terra to the Imperial Palace, where the survivors of the Celestinian and Terran Crusades at last went their separate ways. There, he finally met for one full solar day with his father, the Emperor of Mankind, for the first time in ten millennia.

Roboute Guilliman stood before the Golden Throne and communed with the Emperor. Through their telepathic interaction, the primarch was disturbed by what had become of his father's mental state. He felt that the Emperor had lost all pretenses of humanity and gave off an overwhelming sense of coldness.

The Emperor greeted Guilliman with interest, but as a creator would a long-lost tool, not as a father would with his son. Guilliman feared that the long centuries of suffering had stripped away whatever warmth and humanity the Emperor had once possessed.

None know what was said between them, but when the primarch emerged from the Inner Palace, he declared that he was taking up the mantle of the Lord Commander of the Imperium once more.

Now the first among equals among the High Lords of Terra just as he had been after the Horus Heresy, Guilliman promised the people of the galaxy that he would assemble the greatest fleet and armies seen since the Great Crusade to take the fight to Chaos ... and revive the Emperor's lost dream of a better future for Humanity.

The Era Indomitus had begun.

Indomitus Crusade First Phase

Primaris Astartes Mars

Belisarius Cawl and Roboute Guilliman, deep beneath the surface of Mars, oversee the final stages of development of the Primaris Space Marines.

For ten millennia, the Archmagos Dominus Belisarius Cawl had been working on a task set for him by Guilliman before he was mortally wounded by the Daemon Primarch Fulgrim in the days after the Horus Heresy: a new legion of transhuman warriors. In the time after the Terran Crusade, though the Imperium was poised on the brink of annihilation at the hands of Chaos, his task was at last completed.

The Primaris Space Marines are a new breed of transhuman warriors developed across the span of ten standard millennia by Cawl on Mars. Cawl used the genetic template of the original Space Marines created by the Emperor for His Great Crusade as the starting point for the development of the new Astartes. The Primaris Space Marines are bigger, more physically powerful and possess faster reaction times than their original Astartes counterparts.

The Primaris Marines are new heroes for this, the darkest age in the Imperium of Man's history. These warriors were the next step in the evolution of the Emperor's Angels of Death, and were timely reinforcements for the Imperium's armies as their enemies closed in for the kill in the wake of Abaddon the Despoiler's 13th Black Crusade and the birth of the Great Rift dividing the Imperium in two.

To aid them in battle, these gene-forged warriors were equipped with new arms and armour forged on Mars itself, such as the Mark X Tacticus Pattern Power Armour worn by the Primaris Space Marine Intercessors, which combined the most effective elements of ancestral Horus Heresy patterns of battle-plate with more recent developments in Power Armour technology; the Mark II Cawl Pattern Bolt Rifle, the archetypal firearm of the Adeptus Astartes, now re-engineered, re-crafted and perfected, and the new Redemptor Dreadnoughts.

At the dawn of the Indomitus Crusade called by Guilliman to throw back the forces of Chaos, these phenomenal new warriors joined the lord commander of the Imperium as he fought to liberate the scattered bastions of the Imperium. Some, Guilliman forged into new Space Marine Chapters, whole brotherhoods comprised only of these new transhuman warriors. Others he offered to the existing Space Marine Chapters as much needed reinforcements. Many Chapter Masters welcomed their Primaris brethren into their ranks, accepting the new warriors gladly. Others, though, viewed these new creations with suspicion or outright hostility, claiming that the Emperor's work should never have been meddled with by mere mortals.

Primaris Astartes Stasis

Nearly completed, the gene-forged Primaris Space Marines lie in stasis, waiting to be awakened from their long slumber.

Though they are a step removed from their brothers, the Primaris Space Marines still bear the gene-seed of their primarchs, and some dissenting voices worry how this new type of warrior will react with the known genetic quirks and flaws of some of the more unusual Chapters, such as the Blood Angels and the Space Wolves.

But before the crusade could begin, Guilliman would be forced to defend the homeworld of Mankind for the second time from the forces of Chaos during the Battle of Lion's Gate. As the first Warp Storms of the Noctis Aeterna broke over Holy Terra in the wake of the Great Rift's birth, its pollution-filled skies turned a roiling crimson.

Khorne, heedless of the plans of his brother gods and hungry to prove his superiority, sent forth eighty-eight cohorts of his Daemon legions to assault the Imperial Palace. The Blood God wanted the glory of tearing down the Golden Throne for himself, and so the skies of Terra congealed into bloodclouds that deployed the Red Host directly before the Lion's Gate.

The gun batteries of the Imperial Palace are second to none, yet they alone could not halt this red tide. Led by Roboute Guilliman, the Primaris Space Marines, Adeptus Custodes and Sisters of Silence fought side by side. Although the rash Chaos assault was turned back and broken long before it could reach the Eternity Gate to the Inner Palace, the High Lords of Terra were shaken at the boldness of the foe.

Without the beam of the Astronomican, their arcane machinery and protective devices were not enough to halt the fell powers from materialising even on Holy Terra. Khorne, upon receiving the returning forms of his slain, grew so apoplectic in his rage that his fortress in the Realm of Chaos trembled. So great was the heat from his outburst that the essences of the eight Bloodthirsters that led the failed attack were wholly obliterated.

After his defence of Holy Terra, Roboute Guilliman gathered a new armada that he named the Indomitus Crusade, the largest concentration of Imperial military forces seen since the original Great Crusade over ten thousand standard years before.


Roboute Guilliman maps out his grand strategy to save the Imperium from the myriad xenos and Chaos threats facing it during the Indomitus Crusade.

Along with elements of the Adeptus Custodes, a small contingent of the Silent Sisterhood, and a vast war host of Primaris Space Marines from many newly founded Chapters and the 9 Legions of the Unnumbered Sons, the primarch set a winding course. Strike forces from over a dozen pre-existing Chapters of Space Marines, led by the Imperial Fists, joined the fleet.

Thus began many new legends as Guilliman travelled to aid beleaguered planets, breaking sieges and sweeping away Chaos and xenos invaders alike to bring hope back to the desperate defenders. Among the many worlds aided by the Crusade was Baal, the homeworld of the Blood Angels Chapter, which had come under assault by Hive Fleet Leviathan. During the so-called Devastation of Baal, the fleet of the Crusade arrived in orbit of Baal after the Warp Storms had already consumed the bulk of the hive fleet.

The Imperial reinforcements aided the Blood Angels in cleansing Baal of all remaining trace of the xenos before helping them rebuild, for the strength of the Blood Angels and their Successor Chapters were sorely needed elsewhere in the beleaguered Imperium. Guilliman named Commander Dante, the Chapter Master of the Blood Angels, as the lord regent of the Imperium Nihilus, the half of the Imperium where the Astronomican no longer shone in the wake of the Noctis Aeterna. Dante was ordered to reclaim the worlds of the Dark Imperium in the name of the Emperor.

It was not long before word began to spread, as all those planets that could still receive astropathic messages hailed the return of a hero out of myth. Once more, one of the demigods of the past fought for the Imperium. The Indomitus Crusade's first phase reached its end some twelve standard years later at the Battle of Raukos, when Guilliman at the Triumph of Raukos declared the Imperium Sanctus finally stabilised from imminent collapse.

Afterwards, Guilliman would turn his attention to helping his Realm of Ultramar defeat the forces of the Death Guard Traitor Legion and the Daemonic servants of Nurgle in the Plague Wars.

Plague Wars

After the birth of the Great Rift at the climax of the 13th Black Crusade fractured the Imperium of Man in half, Ultramar came under assault by the servants of the Plague God Nurgle, who had decided to add the whole of Ultramar to his Garden in the Realm of Chaos.

Three star systems to the galactic north of Ultramar, the so-called Scourge Stars, were corrupted by the influence of Nurgle and its planets were transformed into staging grounds for the invasion of Guilliman's stellar empire.

The worlds of Ultramar were attacked from within and without by Nurgle's forces, including an invasion led by the Daemon Primarch Mortarion and his Death Guard Traitor Legion and the Daemonic legions of Ku'Gath, a Great Unclean One.

These so-called "Plague Wars" lasted for several standard years, until following the end of the Indomitus Crusade's first major phase at the Battle of Raukos in ca. 012.M42, Roboute Guilliman, now the ruling lord commander of the Imperium, finally arrived with reinforcements to aid his beleaguered home.

Mortarion's already large invasion force, bolstered by mutants and Chaos Cultists from the Scourge Stars, was accompanied by Typhus and his Plague Fleet alongside a Great Unclean One named Ku'Gath who led a host of 7 Greater Daemons of Nurgle called the "Plague Guard". Their strategy concentrated on taking and holding a few of Ultramar's major worlds such as Iax, Espandor and Konor. The Nurglites only launched smaller raids on the more minor worlds of the sub-sector, always withdrawing before any Ultramarines Astartes were deployed.

The Espandor System was the first to come under siege. All the worlds in the system other than Espandor itself fell to the Forces of Chaos; the Ultramarines bitterly contested Espandor Prime until they were later relieved. One of the Greater Daemons of the Plague Guard, Qaramas, lead this attack, and his partial conquest of the Espandor System prepared the way for the rest of the Nurglite invasion fleet to surge into Ultramar.

Iax was overrun by the Daemons of Nurgle led by Ku'Gath as the bulk of the invasion force came to bear upon it. It had been converted into a so-called "Hospital World" earlier in the conflict to deal with the spread of Nurgle's pathogenic "gifts" across the sub-sector and was therefore susceptible to infiltration by the heralds of Nurgle despite its stringent quarantine measures.

Iax would serve as the base of operations for the Nurglite conquest of Ultramar as Mortarion, the Death Guard and the rest of the Plague Guard ultimately concentrated their forces there late in the conflict.

Macragge suffered from bouts of Chaos-induced unrest as Mortarion led probing attacks on the Ultramarines homeworld. While this did not lead to any widespread destruction or damage to critical facilities, these incidents caused a drop in civilian morale and forced the Ultramarines Chapter Master Marneus Calgar to waste precious time and resources on peacekeeping missions and displays of force to shore up the morale and confidence of Maccrage's suffering civilians.

Typhus and his Plague Fleet overran and captured one of Ultramar's star forts. He was later directed by Mortarion to attack the Ultramarines training world of Parmenio.

Konor came under assault by the forces of the Death Guard, their objective to conquer the crucial system and use it as a springboard for a final attack on Macragge itself.

Guilliman Primaris Plague Wars

Roboute Guilliman leading Primaris Space Marines against the servants of Nurgle during the Plague Wars.

After the Battle of Raukos, Guilliman announced his intention to return to his home realm with thousands of Primaris Space Marine reinforcements and drive back the Chaos assault. First, he cleansed the Hive World of Ardium in the Maccrage System of its Death Guard occupiers.

In the course of that operation he learned that Mortarion was using the ancient artefact known as the Hand of Darkness to craft Plague Engines that were re-animating the dead and turning them into Plague Zombies. Guilliman destroyed the Plague Engine on Ardium and freed the world from the influence of Nurgle.

His next destination was Maccrage itself, his ancient homeworld. He and his Astartes reinforcements, including the Primaris Marines, brought much-needed relief to the weary populace and defenders. Arriving on Maccrage, Guilliman announced that he had made a grave mistake when he had allowed the official borders of Ultramar to shrink so drastically in the days after the Horus Heresy because of his belief that the Space Marines should not rule over large swathes of Mankind.

Instead, he reestablished the ancient ruling Tetrarch Council for Ultramar, and tasked its newly-appointed four Tetrarchs, including his Primaris Space Marine Equerry Captain Decimus Felix and the Ultramarines First Captain Severus Agemman, with beginning to expand the territories of Ultramar to include all of the star systems that had once comprised the Five Hundred Worlds.

After taking stock of the dire situation, Guilliman reorganised the Ultramarines and their mortal auxilia and launched a large-scale counterattack against the invaders. Several Ultramarines Successor Chapters also joined the fight at their primarch's behest, their Chapter fleets engaging the Death Guard and doing their best to keep Ultramar's shipping lanes and supply lines to the broader Imperium safe and secure.

Guilliman first set his eyes on the Espandor System as part of what he named his "Spear of Espandor" campaign, because it served as the main supply line for the Death Guard invasion from the Scourge Stars. He retook each of the lost worlds in the system and destroyed the Plague Engines that were raising the endless tide of Plague Zombies on each of its worlds.

After a ferocious battle in which the Ultramarines Chapter found itself fighting side-by-side with their Primaris Astartes brethren for the first time, the forces of Nurgle were routed from Espandor. Guilliman decisively ended the battle by slaying the Great Unclean One Qaramas with the Emperor's Sword and destroying the last Plague Engine in the system. The Espandor System had been cleansed of the taint of the Plague God and the forces of Nurgle were now cut off from their base in the Scourge Stars.

With their supply lines to the Scourge Stars cut, their Plague Engines disappearing and slowly eliminating the constant tide of undead reinforcements, and new Imperial reinforcements pouring into Ultramar with each passing solar day, Mortarion found himself on the wrong side of what had become a war of attrition.

Guilliman had successfully cut the Death Guard off from resupply and would now proceed to cut their forces to pieces, one system at a time. With this in mind, Mortarion decided to throw all his remaining forces at a single target in the hopes of reversing the tide.

Maccrage was still too heavily defended for the forces of Nurgle to carry out a successful assault, so Mortarion decided that the Plague God's servants would target the Ultramarines training world of Parmenio. This battle saw the biggest armoured clash between the Chaos and Imperial forces during the war.

The largest star fort in Ultramar, Galatan, attempted to provide support but was engaged by Typhus' Plague Fleet and was boarded by a contingent of Traitor Marines, leading to the death of the Novamarines' Chapter Master Bardan Dovaro in the vicious fighting.

On the surface of Parmenio, however, the Ultramarines slowly gained the upper hand. Guilliman killed Ku'Gath's lieutenant, Septicus, and shattered his daemonic Plague Guard, an action that finally gave the Emperor's servants the upper hand in the conflict. With the campaign at last in hand, Guilliman turned to the hunt for his traitorous brother.

Guilliman then finally led a relief force to benighted Iax. Having not discovered Mortarion leading his forces on either Parmenio or Espandor, the Lord Commander of the Imperium was determined to hunt down his traitorous brother once and for all.

The climactic battle of the conflict took place on Iax, where Guilliman and Mortarion personally fought each other to a brutal stalemate amongst the ruins of the Hospital World. In the wake of this battle, as the Nurglite forces in Ultramar continued to lose ground on every front, Mortarion and the Death Guard were summoned back to the Scourge Stars.

Nurgle's outpost in realspace had come under assault from the forces of Khorne in what would become the War in the Rift, another campaign in the endless Great Game between the Ruinous Powers as they maneuvered for advantage against each other.

The Death Guard withdrew from Iax under the cover of a Virus Bomb attack on the Imperial forces and Nurgle's remaining servants ultimately retreated from Ultramar, but the threat of a renewed attack from the Scourge Stars was now a persistent threat.


Pre-Heresy Era

Marenus Calgar model 2

The Primarch Roboute Guilliman arrayed in his fearsome panoply of war during the Horus Heresy.

  • Armour of Reason - Known in the legends of his Legion as the "ever-reforged" armour, it was said that Roboute Guilliman himself had this set of Artificer Armour remade and adapted countless times if ever a flaw or weakness was discovered in battle, and at various times the artisanship both of Mars and his fellow Primarchs Vulkan and Perturabo influenced its design in the days before the sundering of the Imperium in the fires of the Heresy.
  • Gladius Incandor and the Hand of Dominion - As with many of his brother primarchs, Roboute Guilliman possessed a vast selection of weapons and wargear, both to wield on the battlefield as desire and need dictated, and in Guilliman's case also to study and contemplate, so that his arts of war and that of his Legion could be continuously honed and improved. Perhaps the most iconic of these arms were the Power Fist known as the Hand of Dominion and the glittering, master-crafted Power Sword known as the Gladius Incandor. These were not merely weapons of surpassing quality, but symbols for the Ultramarines Legion of its master's might and authority.
  • The Arbitrator - One of Roboute Guilliman's favoured side arms when in open battle was a heavily customised Combi-bolter which he was able to wield as deftly as one of his Astartes might handle a pistol. Dubbed by him the Arbitrator for the matters it settled, it was tooled to tolerances beyond any but the archmagi of the Mechanicum could fathom, while its bolt shells were hand-crafted by the finest Ordnancer-wrights of the XIII Legion's forges and fitted with micro-atomantic compression warheads.
  • Cognis Signum - The Cognis Signum was an advanced array of sensory devices, cogitator-assisted communications, and telemetry arrays built into the suit of power armour worn by the primarch by the Mechanicum, and was similar to those used in its own Thallax cybernetic warriors.
  • Frag Grenades - The primarch always made sure to keep several of the simple, but effective, Frag Grenades on his person for use where appropriate during battle.

Era Indomitus


The resurrected Primarch Roboute Guilliman, arrayed in his new panoply as he prepares to lead the Imperium of Man in throwing back the forces of Chaos in the Era Indomitus of the 41st Millennium.

  • Armour of Fate - Crafted by the armourers of the Adeptus Mechanicus, its inner workings enhanced with advanced life-sustaining technologies, this glorious suit of highly advanced and unique Artificer Armour fits Guilliman perfectly, and protects him from even the most dolorous of blows.
  • Hand of Dominion - A more advanced version of the mighty powered gauntlet worn by Guilliman during the Horus Heresy, this godly Power Fist not only allows the primarch to crush the life from his foes like its original incarnation, but to annihilate them in storms of armour-piercing gunfire with its built-in bolter.
  • Iron Halo - The Iron Halo is a halo-shaped ring that is positioned above the head of the wielder, usually mounted on the backpack of Space Marine power armour but sometimes mounted in the gorget. The Iron Halo is a prestigious honour that is granted only to the most exceptional of the Astartes within a Space Marine Chapter as a reward for uncommon initiative and valour. It is most often worn by the Chapter's captains and Chapter Master, though Veteran Astartes and sergeants can also earn the right to add it to their armour in certain circumstances. The Iron Halo appears to share the same basic technological mechanisms as the Space Marine Chaplain's Rosarius, as they both produce a protective force field effect using gravitic and now poorly-understood Conversion Field technology. Guilliman wears a specially-crafted Iron Halo whose protective field has been resized for his greater height and mass than a normal Astartes.

Canon Conflict

As originally chronicled in the Dark Imperium novel series by Guy Haley published in 2017-2018 early in the 8th Edition of Warhammer 40,000, the Indomitus Crusade lasted for roughly 100 standard years and ended with the Plague Wars.

However in 2021 Black Library retconned the events of the novels to take place only 12 standard years after the crusade had begun, now with no end date for the conflict.

This change now places the events of the Plague Wars in circa 012.M42 early in the Indomitus Crusade by the chronology of the original Imperial Calendar.


See Also


  • Codex: Space Marines (5th Edition), pp. 7-9, 12-15, 24, 84
  • Codex: Space Marines (3rd Edition), pg. 36
  • Codex: Ultramarines (2nd Edition), pp. 4, 7-9, 11-13, 15
  • Dark Imperium (Novel) by Guy Haley, Chs. 10, 17, 20, 22
  • Deathwatch: Core Rulebook (RPG), pp. 53-54, 200
  • Deathwatch: First Founding (RPG), pp. 67-73
  • Horus Heresy - Volume II: Visions of Darkness
  • Horus Heresy: Collected Visions
  • Index Astartes III, "Warriors of Ultramar - The Ultramarines Space Marine Chapter"
  • Insignium Astartes: The Uniforms and Regalia of the Space Marines
  • The Horus Heresy - Book Five: Tempest (Forge World Series) by Alan Bligh, pp. 70-82, 96-99, 238-239
  • Gathering Storm - Book Three - Rise of the Primarch (7th Edition), pp. 4-93
  • The Unremembered Empire (Novel) by Dan Abnett
  • Angels of Caliban (Novel) by Gav Thorpe
  • Ruinstorm (Novel) by David Annandale
  • Slaves to Darkness (Novel) by John French, Chs. 1-3
  • Warhammer 40,000: Rulebook (8th Edition), pp. 50-53, 154-159, 167
  • Warhammer 40,000 Rulebook (6th Edition), pp. 161, 187, 403
  • Warhammer 40,000 Rulebook (5th Edition), pg. 134
  • White Dwarf 40 (December 2019), "Worlds of Warhammer" by Phil Kelly, pg. 11
  • White Dwarf 264 (AU), "Index Astartes - Ultramarines"
  • White Dwarf 263 (US), "Index Astartes - First Founding: Warriors of Ultramar - The Ultramarines Space Marine Chapter", pp. 18-25
  • White Dwarf 97 (US), "Index Astartes - Ultramarines" by David Wise & Rick Priestley, pp. 39-49
  • Defenders of Ultramar (Graphic Novel) by Graham McNeill, Issue 1, pg. 5
  • The First Hertic (Novel) by Aaron Dembski-Bowden
  • Age of Darkness (Anthology) edited by Christian Dunn, "Rules of Engagement" by Graham McNeill
  • Know No Fear (Novel) by Dan Abnett
  • Betrayer (Novel) by Aaron Dembski-Bowden
  • Roboute Guilliman: Lord of Ultramar (Novel) by David Annandale
  • The Warhammer Preview Online: Black Library, Interview with Guy Haley December 5, 2020
  • Forge World - Roboute Guilliman, Primarch of the Ultramarines
  • Warhammer Community - A New Breed of Hero
  • Warhammer Community - Primaris Space Marines: FAQ.
  • Warhammer Community - Black Library Live: The Big Reveals
The Primarchs
Loyalist Primarchs Lion El'JonsonJaghatai KhanLeman RussRogal DornSanguiniusFerrus ManusRoboute GuillimanVulkanCorvus CoraxLost Primarchs
Traitor Primarchs FulgrimPerturaboKonrad CurzeAngronMortarionMagnus the RedHorusLorgarAlpharius Omegon
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