The Eye of Horus, symbol of the Archtraitor and Warmaster Horus Lupercal

Presented below is the Horus Heresy Chronology, an exhaustive listing of all known campaigns and battles that occurred during the nine-year-long, galaxy-wide conflict known as the Horus Heresy in the early 31st Millennium.

By no means is this list complete, as much of the information presented in various canon sources is often ambiguous and even at times contradictory.

Therefore, this is merely a rough guide to the chronological order of the events during this conflict and no date should be taken as absolutely final should new evidence come to light.

Prelude to Heresy

Below is a chronology of the events immediately preceding the start of the interstellar civil war later called the Horus Heresy. Though Horus turned to the service of Chaos several standard years before the start of the conflict, the Heresy only officially began with the Istvaan III Atrocity.

  • 003.M31 Contact Lost with the Istvaan System - Six Terran years after the last official communiqué from Istvaan III, a Death Guard patrol ship on the outer edge of the XIV Legion's fleet picked up an incomplete astrotelepathic transmission which indicated that Istvaan III was in open religious rebellion against the Imperium. The Imperial planetary government had collapsed, and the Planetary Governor Vardus Praal, now a turncoat and perhaps become a mutant or psyker, was leading the revolt.
  • 004.M31 Plague Moon Campaign and the Fall of Horus - The Warmaster Horus is grievously wounded while fighting rebels on the moon of Davin. He is healed within the ancient Serpent Lodge on the moon but though his life is saved, his soul is forfeit to the Ruinous Powers. From this day forth he makes his plans to bring the Imperium to ruin and topple the Emperor from power. Though his treachery and malign intent remain hidden, he begins his far-reaching conspiracy to suborn those of his brother Primarchs' Space Marine Legions and the other military forces of the Imperium who will aid him and neutralise the threat of those who will not serve him where he can. He prepares in secret over the next two Terran years to fight a sudden and ruthless galactic civil war.
  • 004-009.M31 Signus Cluster Campaign - The bulk of the Blood Angels Legion is dispatched through the machinations of the Warmaster Horus to the distant Signus Cluster to put down a local uprising. Knowing the IX Legion will never join his cause and fearing their Primarch Sanguinius, Horus sets his trap at Signus Prime, where the Blood Angels are beset by a foe none have ever faced before, the daemonic legions of the Ruinous Powers, and assailed by terrifying psychic assaults and distortions of reality.
  • 004.M31 The Destruction of Olympia - While the Iron Warriors Legion was cleansing the world of Gugann of a major infiltration of the infamous xenoform known as the Hrud, the long-lived Satrap of Olympia died. With the death of the Tyrant of Lochos, the Iron Warriors' homeworld erupted into infighting and insurrection. The population had taken up arms against the Imperium following many solar years of relentless anti-Imperial propaganda by the dead Tyrant. Tired of repeatedly having to prove himself, and enraged at the disregard of his fellow Legiones Astartes who have left his Legion to carry out dishonourable work as garrison forces, the Primarch Perturabo and the Iron Warriors brutally suppressed the rebellion on the streets of the city-states of Olympia. No one was spared. It was the principle of surrender or no quarter, and the Iron Warriors had grown accustomed to granting no quarter. Perturabo watched as the Olympian fortifications in which he had once taken such pride were overcome. By the time the massacre was over, Olympia had been culled into slavery. Five million civilians had been killed in the process. Horrified at what he had done in his rage, Perturabo knows the Emperor will never forgive him. But Horus offers him another path...
  • 004.M31 Destruction of the Auretian Technocracy - The already corrupt Horus assassinates the Auretian Technocracy's leader, the Fabricator Consul, who represented the independent human government, in order to obtain highly-coveted lost Standard Template Construct data. Horus later uses this illicitly recovered STC database to entice Fabricator-General Kelbor-Hal of the Mechanicum to join the Traitor cause. This plants the seeds of the Dark Mechanicum's birth and the eventual Schism of Mars.
  • 004.M31 Battle of Tarsus -The Primarch Fulgrim meets with the renowned Aeldari Farseer Eldrad Ulthran of Craftworld Ulthwé on the Maiden World of Tarsus, in which the Farseer attempted to warn Fulgrim of the Warmaster Horus' corruption by Chaos. Ultrhan explains that Horus has been fallen to the Dark Gods after being wounded by a malefic Chaos blade known as the Kinebrach Anathame at the hands of the Traitor Eugen Temba upon Davin's Nurgle-corrupted moon. Fulgrim reacted with violent outrage at the Farseer's accusations due to his close kinship with his brother Horus. This outrage was further enhanced by the corrupting influence of Fulgrim's daemon-possessed Blade of the Laer, which darkly influenced the Primarch to reject the Aeldari's truth and provoked Fulgrim into launching an unprovoked and furious attack on Eldrad and his retinue alongside his Emperor's Children Captains and his personal Phoenix Guard. In the battle that ensued, the Emperor's Children slew both the revered Aeldari Wraithlord Khiraen Goldhelm and a potent Avatar of Khaine, which forced the Farseer and the other Aeldari troops to sorrowfully withdraw, as they realised that Chaos had already claimed yet another of the Mon-Keigh's Primarchs. Yet they succeeded in killing all of Fulgrim's elite personal Phoenix Guard before their departure. Believing the Aeldari had proven themselves a treacherous xenos race that sought to divide and conquer the Imperium by spreading such lies about its leaders, Fulgrim, again under the increasing influence of the Laer daemonblade, ordered the destruction of several other beautiful Aeldari Maiden Worlds using hideous Virus Bombs.
  • ca. 004.M31 Battle of Deep Orbital DS191 - Following his delegation to the 63rd Expeditionary Fleet, Fulgrim announced to his senior commanders that he would lead a small force to join his brother Primarch Ferrus Manus and his Iron Hands at Callinedes IV in the Callinedes System under the pretense of clearing it of an Ork infestation. The Emperor's Children Primarch spearheaded the assault during the pacification of Deep Orbital DS191, leading the 1st, 2nd and 3rd Companies. During the assault, Captain Solomon Demeter, commander of the Emperor's Children's 2nd Company, found himself unsupported by the 1st and 3rd Companies as the battle-plan had laid out. Overextended and in real danger of being cut off and destroyed, the 2nd Company was only saved from certain destruction by the unplanned and timely arrival of the 10th and 13th Companies under the commands of Captains Saul Tarvitz and Lucius, two junior officers that Demeter had found himself associating more and more with as he was systematically frozen out by the III Legion's high command. A dark shroud hung over Lord Commander Vespasian after witnessing these dishonourable actions. He felt obliged to act after he observed Solomon Demeter's 2nd Company being intentionally abandoned by both Captain Kaesoron's and Vairosean's companies. It was a decision that would cost the honourable Astartes his life when he was murdered by the Chaos-corrupted Fulgrim himself.
  • 734.004.M31 The Fall of Prospero - Magnus the Red, Primarch of the Thousand Sons Legion, learns of his brother Horus' fall to Chaos and attempts to warn the Emperor using psychic arts forbidden by the edict of the Council of Nikaea. His psychic transmission inadvertently unmakes the psychic wards of his father's attempt to create an Imperial extension to the Aeldari Webway. The Emperor was secretly building this extension deep beneath the Imperial Palace on Terra with the aid of the Golden Throne and the Mechanicum. With the wards collapsed, daemons begin to flood into the corridors of the Imperial Webway and the Emperor is forced to remain on the Golden Throne to prevent the breach from spilling into the Imperial Palace itself. The Space Wolves, Sisters of Silence and a detachment of the Legio Custodes are ordered to form a Retribution Fleet and bring Magnus to Terra from Prospero in chains to answer for his violation of the Edicts of Nikaea forbidding him from using sorcery. Seeing an opportunity, the Warmaster Horus intervenes and convinces his brother Leman Russ that Magnus' crime is so dire that his life is forfeit and Magnus should never set foot upon Terra alive. The Space Wolves assault the Thousand Sons' homeworld and raze its capital city of Tizca to ashes. While Magnus escapes into the Warp with the aid of Tzeentch, the Changer of Ways, his Legion is reduced to but a thousand warriors. Bitter at his treatment by the Emperor, Magnus schemes to join Horus' rebellion.
  • 005-006.M31 Schism of Mars - Fabricator-General of the Mechanicum Kelbor-Hal turns against the Imperium and plunges Mars into civil war, those loyal to Terra and the Emperor as the Omnissiah forced to abandon the Red Planet. Elsewhere, the Schism of Mars sunders the feudal order of the Mechanicum and its bonds with the Imperium. Many Forge Worlds side with the Traitors, others with the Emperor and still others declare independence from either side. So likewise are the Mechanicum's Titan Legions, the Skitarii Legions and the powerful Forge World Taghmata riven with division.
  • 005.M31 Battle of Istvaan Extremis - The elite 1st Company of the Emperor's Children Legion fought in concert with the Death Guard Legion's 7th Battle Company under the command of Battle-Captain Nathaniel Garro, against traitorous forces on Istvaan Extremis, the outermost planet within the Istvaan System. Whilst fighting against a powerful Slaaneshi psyker known as a Warsinger, Garro sustained serious injuries; crushing damage to his torso and arm as well as the loss of his right leg from the mid-thigh down. He was only saved from certain death by the timely ministrations of the Emperor's Children Legion's Chief Apothecary Fabius. Taking stock of the desperate situation, the Emperor's Children Lord Commander Eidolon made use of a hitherto unknown ability -- a modified tracheal implant bonded with the Lord Commander's vocal chords that allowed him to produce a nerve-paralysing shriek similar to that employed by certain warrior breeds of the xenos Laer. This powerful ability killed the Warsinger and helped the Astartes carry the day.

The Heresy Chronology

Presented below is a chronological listing of the events of the Age of Darkness which fell upon the Imperium of Man during the Horus Heresy of the early 31st Millennium. The following information was compiled by manifold and diverse hands at the order of Malcador the Sigillite and the Acting Council of Terra following the outbreak, as well as during, the major events of the Horus Heresy. As more information surrounding this dark era of human history is uncovered in newly discovered Imperial records, it will be added to the chronology.

  • 008.M31 Battle of Nuceria - At the climax of the Battle of Nuceria during the conclusion of the Shadow Crusade, whilst in combat with Roboute Guilliman, the Primarch Angron of the World Eaters reaches a nadir of pain, bitterness and rage which forms a conduit between him and the Warp. Guilliman and his Ultramarines are forced to withdraw as his brother is ravaged by Empyreal energies and is transformed into a Daemon Prince of Khorne, the Blood God.
  • 011.M31 The Marches of Madness - The World Eaters made seemingly senseless raids on population centres across the Ultima Segmentum. Their brutal attacks are aimed at causing maximum human casualties, ignoring both infrastructure and military targets. The attacks are accompanied by unseasonal violent storms and unnatural crimson cloud bursts. The World Eaters have come fully under the grip of Khorne and now seek only more blood for the Blood God's unending thirst.
Participating Force(s)
005-006.M31 Istvaan III Atrocity Sons of Horus, Emperor's Children, World Eaters, Death Guard Traitor Victory Horus musters four entire Astartes Legions to put down a rebellion against Imperial rule at Istvaan III, and having turned the Primarchs of those Legions to his treacherous cause, engineers the purging of tens of thousands of Legionaries not trusted to follow them into treason because of their continued loyalty to Terra and the Emperor. The ancient magicks of the Sirenhold are unleasged against the forces of the Sons of Horus, Emperor's Children, Death Guard and World Eaters. The battle against the rebel governor Vardus Praal and his Slaaneshi Warsingers is won, but is ultimately in vain when the four Legions unleash a terrible Virus-Bombing of Istvaan III while the Loyalist Astartes are engaged against the rebels. All does not go to plan, however, and many of the Loyalists survive to force Horus to engage them in a vicious battle among the ruins of the planet's capital, the Choral City, before they are finally wiped out by orbital bombardments. At the same time, a small number of these Loyalists escape the carnage to carry word of the Traitors' actions to Terra aboard the frigate Eisenstein. This action marks the formal start of the great conflict that will be named the Horus Heresy.
005.M31 Flight of the Eisenstein 70 Loyalist Death Guard Pyrrhic Loyalist Victory Nathaniel Garro, Battle-Captain of the Death Guard's 7th Great Company, flees Istvaan III after having witnessed the Warmaster Horus' treachery first-hand. He braves the Warp to escape the Traitor forces who pursue him in order to bring word to the Emperor of his once favoured-son's duplicity. He encounters Primarch Rogal Dorn and his Imperial Fists and informs Dorn of the Istvaan III Atrocity. Dorn brings Nathaniel Garro to the Somnus Citadel on Luna, home of the Sisters of Silence. Garro is later brought before the Regent of Terra, Malcador the Sigillite and recounts his tale of woe. The Imperium begins to fortify itself against the inevitable attack of the Traitor Legions. Nathaniel Garro is chosen to become the Agentia Primus of Malcandor's newly formed Knights-Errant.
005.M31 Battle of Diamat Dark Angels contingent vs. Traitor Imperialis Auxilia, fleet assets and Sons of Horus contingent Loyalist Victory When word reaches the Dark Angels of the Istvaan III Atrocity, Lion El'Jonson and the I Legion are bogged down fighting a campaign against the Gordian League. Therefore, the Lion leads a small war fleet of 16 vessels against the Forge World of Diamat, in order to seize Ordinatii heavy siege engines, and deny them to the Traitors. He encounters some resistance from vessels loyal to the Traitor cause, as well as Traitor Imperial Army forces and a Sons of Horus company on the planet's surface. The Lion orders the destruction of the planet's primary forges, which annihilates the Traitor forces in a great conflagration and denies to Horus Diamat's manufacturing capabilities. In the battle's aftermath, the Lion encounters the Iron Warriors' Legion fleet, led by Perturabo, who are on their way to Istvaan V to "pacify" the treacherous Warmaster. Unaware of their true loyalties, the Lion unwittingly hands over the captured Ordinatii to be used against Horus to those who actually intend to join the Archtraitor's cause.
566.006.M31 The Drop Site Massacre of Istvaan V Alpha Legion, Death Guard, Emperor's Children, Night Lords, Sons of Horus, Word Bearers, World Eaters, Iron Hands, Raven Guard, Salamanders Traitor Victory With Terra warned of the Warmaster Horus' treachery at Istvaan III, eight entire Space Marine Legions, half of the known forces of the Legiones Astartes, are ordered by Terra to crush the Traitors' rebellion at Istvaan V, but unbeknownst to the rest, Horus has already turned three of them to his service and ensured the fourth is delayed. The first wave of Loyalist Legions -- the Iron Hands, Raven Guard and Salamanders -- makes planetfall but is betrayed by the second wave coming behind them -- the Alpha Legion, Night Lords, Iron Warriors and elements of the Word Bearers -- in the bloodiest three solar hours of war ever fought by the Legiones Astartes. In the aftermath of the great betrayal, three Legions are almost entirely wiped out, one Primarch, Ferrus Manus, is slain by Fulgrim and two others -- Vulkan and Corvus Corax -- are missing in action. The survivors of the Iron Hands, Raven Guard and Salamanders who manage to escape off-world or remained elsewhere in the galaxy become known as the "Shattered Legions."
ca.006.M31 Battle of Ravendelve Raven Guard vs. Alpha Legion infiltrators Pyrrhic Imperial Victory Following the calamitous events on Istvaan V and the surviving Raven Guard's flight to Terra to bring word of the disaster, the shattered XIX Legion returned to their homeworld of Deliverance. Unknown to them, the insidious Alpha Legion had inserted several of their own Legionaries into the Raven Guard Legion, surgically disguised as Raven Guard Astartes who had died on the black sands of Istvaan V. Gathering intelligence on the Primarch Corax' efforts to reconstitute his Legion utilising a sample of pure Primarch DNA given to him by the Emperor Himself, the Alpha Legion operatives patiently waited until the Raven Guard had achieved a genetic breakthrough. In the meantime, they fomented rebellion amongst the old tech-guilds of Kiavahr, the Forge World that the moon of Deliverance circled, while assembling Alpha Legion forces nearby for an unsuspected surgical strike. The Alpha Legion successfully tainted the Primarch DNA, which resulted in the disastrous mutation of newly-inducted Raven Guard Aspirants into hideously transformed creatures. At the same time, the Alpha Legion's plans reached their climax. The Kiavahr rebellion was well under way, supported by the newly-arrived Alpha Legion forces, who were camouflaged as Raven Guard. The Loyalist Raven Guard successfully put down the rebellion and killed all the Alpha Legion operatives, but were no closer to reconstituing their Legion's numbers or making a difference in the fight against Horus.
ca. 006-009 Imprisonment of Vulkan Primarch Vulkan vs. Primarch Konrad Curze Inconclusive The Salamanders' Primarch Vulkan managed to survive the nucleonic bombardment of the Urgall Depression on Istvaan V, due to his unknown regenerative abilities as an immortal Perpetual, a status he had inherited from his genetic father the Emperor, also a Perpetual. When Vulkan finally awoke in the aftermath of the explosion, he found himself surrounded by hundreds of Iron Warriors and Night Lords Legionaries. Prepared to fight to the death, the Traitor Marines proceeded to shoot, stab and bludgeon the Primarch into unconsciousness. Seeing the opportunity to torment his brother, Konrad Curze took Vulkan prisoner, and secured him aboard his flagship Nightfall. Over a period of several solar months, Curze would proceed to torture Vulkan mercilessly in an attempt to break his body, mind and spirit. But eventually Vulkan effected his escape, and with his warhammer Dawnbringer, was able to teleport himself to the upper orbit above the capital world of the Realm of Ultramar -- Macragge. Before burning up in the planet's atmosphere upon reentry, he was confident that he would wake up in the care of his cousins, for immortality was his birthright.
006.M31 The First Battle of Paramar Alpha Legion, Legio Fureans and Taghmata Satarael (Dark Mechanicum) vs. Loyalist Iron Warriors (77th Grand Company), Legio Gryphonicus, Mechanicum, Skitarii Traitor Victory Alpha Legion forces allied with the Traitor Dark Mechanicum of Taghmata Satarael and the Titans of the Legio Fureans mount a surprise attack on the strategically vital lynchpin star system of Paramar before their true allegiance becomes known to the defenders. Paramar is a vast arms cache of the Great Crusade and a vital Imperial communications hub. The Pharaeon of Paramar, its primary void station, is quickly taken, but a full planetary assault of Paramar V becomes necessary as Loyalist Mechanicum and Legio Gryphonicus Titan forces, as well as the unexpected intervention of a Loyalist cadre of the Iron Warriors Legion, offers the invaders strong resistance. The valiant defence, however, is ultimately overwhelmed and Paramar falls to the Traitors, cutting off much of the most stable transit routes to the northern Imperium.
006.M31 The Sundering of Zhao-Arkad
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006.M31 Battle of Lesser Damantyne Loyalist Iron Warriors vs. Traitor Iron Warriors Pyrrhic Traitor Victory When the Iron Warriors Warsmith Krendl arrives at Lesser Damantyne with the Iron Warriors 51st Expeditionary Fleet to secure the formidable fortress, known as the Schadenhold, as a resupply point for the Warmaster Horus' Traitor Legions, its Loyalist Iron Warriors commander, Warsmith Barabas Dantioch refuses to comply. This results in an internecine conflict between the two opposing Iron Warriors forces. Dantioch commanded his meagre forces against the entire might of the 51st Expeditionary Fleet and the 14th Grand Company of the Iron Warriors for 366 solar days, until the Traitors deployed an Imperator-class Titan to destroy the Schadenhold. Though the fortress falls, Dantioch and the surviving Loyalist Iron Warriors teleport aboard the Traitors' flagship and commandeer it, and flee towards Terra.
ca. 007.M31 Raid on Cruciax Raven Guard contingent vs. Word Bearers contingent Loyalist Victory The Raid on Cruciax, a world that harboured a listening post of the Word Bearers Legion, marked the Raven Guard's return to the battlefield after the crippling losses suffered during the Drop Site Massacre. Intended as a field test to further assess the capabilities and discipline of the new contingent of the XIX Legion, the Raptors, the raid was a full success, wiping-out the Word Bearers garrison and destroying the facility in less than twenty solar minutes. The first three hundred members of the Raptors, who were all genetically perfect, were declared battle-ready following this action and the Raven Guard quickly put its eye on a more important target -- the Siege of the Perfect Fortress on the world of Narsis.
007.M31 Siege of the Perfect Fortress Raven Guard, Imperialis Auxilia & Mechanicum assets vs. large Emperor's Children contingent Loyalist Victory Located on the world of Narsis, the so-called "Perfect Fortress" had been erected by the III Legion, the Emperor's Children, during the Great Crusade-era. Following the XIX Legion's catastrophic losses and the ill-fated attempt to quickly replace these losses, Corvus Corax decided that his Legion would assail the highly symbolic location to prove that it was still a formidable fighting force. Through the use of Corax' superlative military tactics and stratagems, the so-called "Perfect Fortress" falls within the solar day. This highly symbolic action not only marked a severe defeat for the notorious Traitors of the III Legion, but also the return of the XIX Legion to the front lines during the Heresy. It was purely an act of spite against Horus, and even though its choice nearly brought it to extinction, the Raven Guard still opposed him and proved to be a thorn in the Archtraitor's side.
007.M31 First Siege of Hydra Cordatus Iron Warriors and Dark Mechanicum assets vs. Imperial Fists contingent, Imperialis Auxilia forces and surviving human population Traitor Victory Shortly after the disastrous events of the Drop Site Massacre of Istvaan V had played out to their tragic conclusion, the traitorous Iron Warriors Legion saw the opportunity to humble their hated rivals, the Imperial Fists, upon the isolated world of Hydra Cordatus. The Iron Warriors make planetfall and proceed to be held at bay for nearly three solar months, thanks to the courage of its defenders, the geography and the ingenuity of the fortress builders of the Cadmean Citadel. The few surviving Imperial Fists defenders were slaughtered to a man and the surviving refugees were enslaved by the Iron Warriors before they moved on to their next objective. Hydra Cordatus was reduced to a barren Desert World by the ferocity of the Traitor Legion's assault.
007.M31 Battle of Phall Iron Warriors vs. Imperial Fists Pyrrhic Traitor Victory Having been cast off-course and stymied by Warp Storms en route to Istvaan V by the machinations of the Warmaster Horus' dark allies, the Imperial Fists retribution fleet is becalmed for long solar months at the Phall System. Only by maintaining a constant state of readiness and the genius of their commander is the fleet saved from utter destruction when the Traitor Iron Warriors attack. At the height of the engagement, an astrotelepathic message from Terra finally breaks through the turbulent Warp, as Rogal Dorn, the Primarch of the Imperial Fists, orders his fleet to return to Terra at once.
ca. 007.M31 The Angel Exterminatus Iron Warriors & Emperor's Children vs. Aeldari Pyrrhic Traitor Victory Both the Iron Warriors and Emperor's Children enter the great Warp rift named by Perturabo as the "Eye of Terror," on a quest to seek out an ancient Aeldari weapon known as the Angel Exterminatus. They are led deep within the hellish region where the Empyrean bleeds into realspace, where they discover the remnants of an Aeldari Crone World called Iydris. While exploring the planet's ancient ruins for the legendary weapon, they are set upon by guardian Ghost Warriors and other Aeldari Wraith constructs and by elements of the Shattered Legions that have been tracking their activities for many solar months. Unknowingly, Fulgrim had been using his brother's life force in order to finally achieve daemonic apotheosis, and he becomes the first Primarch to ascend to the position of Daemon Prince during this quest. The act destroys Iydris, and releases so much energy that a black hole singularity is formed. Perturabo escapes from the world with his Legion after watching Fulgrim and his warriors teleport somewhere else, and their fleet dives directly into the heart of the black hole. They emerge on the other side of the galaxy, near the verdant world of Tallarn.
007-009.M31 The Shadow Crusade World Eaters, Word Bearers vs. Ultramarines Inconclusive The Word Bearers and World Eaters invade the Five Hundred Worlds of Ultramar with the aim of utterly destroying the domain of the Ultramarines and drawing Loyalist forces away from the Warmaster Horus' advance on Terra. During the conflict, which centres around the perfidious attack of the Word Bearers at the Calth Muster, scores of worlds are ravaged and the involvement of the Ruinous Powers in aid of the Traitor cause is first widely manifested in open war, transfiguring both of the Traitor Legions involved.
007-009.M31 The Manachean War and the Dark Compliances Various Traitor & Loyalist Legiones Astartes, Shattered Legions & Blackshield forces Traitor Victory His treachery fully revealed at last, the Warmaster Horus begins his relentless advance on Terra, forcing his Dark Compliance of countless regions across the northern Imperium to provide his forces with a resource base to fight what will now become a protracted and relentless interstellar civil war. Foremost among his targets are the Manachean Commonwealth, the Coronid Deeps and their surrounding regions, where a particularly savage campaign is conducted by the Sons of Horus and Death Guard which brings the economically vital worlds of the Manachean Commonwealth to fuel the Traitors' cause. This wider campaign also places the fleet anchorage of Port Maw under the Warmaster's talon and sees the stubbornly Loyalist Forge Worlds of Lucius and Mezoa isolated and besieged, while the Traitor-aligned Forge World of Cyclothrathe begins to carve out its own pocket empire in the region.
007.M31 Destruction of the Furious Abyss Small ad hoc Loyalist strike force of various Space Marine Legions vs. Word Bearers contingent Loyalist Victory Following the destruction of the Auretian Techocracy and securing of their rare STC templates, Lorgar, Primarch of the Word Bearers Legion, secured a secret alliance with the traitorous Fabricator-General Kelbor-Hal. He commissioned the Dark Mechancium to construct a trio of mighty vessels built for the service of his Legion. The Furious Abyss was the first such vessel of its kind. The Word Bearers had been secretly ordered by the rebellious Warmaster Horus to bring their unfettered wrath down upon their hated rivals, the Ultramarines Legion. The Furious Abyss was to play an instrumental role in the Battle of Calth and the Traitor Legion's destructive campaign that was intended to see the Ultramarines capital world of Macragge destroyed. But before the mighty Battleship could reach its destination, the secret of its existence had been discovered. The Word Bearers' vessel was infiltrated by a small Loyalist strike force of Space Marine Legionaries, who proceeded to sabotage the ship's plasma generatorium, which began a chain-reaction that resulted in the destruction of the massive vessel.
007.M31 The Calth Conjunction, Battle of Calth and the Birth of the Ruinstorm Ultramarines & Word Bearers Pyrrhic Traitor Victory Mustering at the world of Calth in Ultramar on orders issued by the Warmaster Horus before the Istvaan III Atrocity, the Ultramarines and Word Bearers prepare for a campaign against the Orks of the Ghaslakh xeno-hold. The Ultramarines are unaware of the Word Bearers' true allegiance and utterly unprepared for betrayal, and suffer horrific losses. The Traitors' real objective is the murder of Calth's Veridia star as an offering to the Ruinous Powers that would bring about the birth of the Ruinstorm, a Warp tempest so large it would sever the galaxy in half and render all long-range Warp travel unpredictably dangerous, and trans-luminal astrotelepathic communication all but impossible. This paves the way for Horus' rapid advance on Terra. The so-called "Age of Darkness" begins.
007-017.M31 The Underworld War on Calth Ultramarines, Mechanicum, Legio Praesagius vs. Word Bearers, Legio Suturvora, elements of Traitor Imperialis Militia & Chaos Cultists Loyalist Victory Following the events of the Battle of Calth, the Word Bearers perform one last act of spite and cause the planet's primary star to become unstable. The surface of Calth is ravaged by the radiation emitted by the slow death of the Veridia star. The continuing Battle of Calth between trapped forces of those Ultramarines and Word Bearers still locked in a death-struggle descends into the extensive arcologies deep beneath the planet's surface. This so-called "Underworld War" grinds on for ten solar years before the last of the Traitors is finally hunted down and slain, a period that extends beyond even the end of the Heresy itself.
570.007.M31 Return of Cassian Dracos Salamanders contingent N/A Still ignorant of the events that occurred on Istvaan V, Lord Chaplain Nomus Rhy'tan despatches Chaplain-Lieutenant Xiaphas Jurr and 30 Firedrakes aboard the Ebon Drake to ascertain the fate of their Legion. When the Ebon Drake arrived at the black sands of Istvaan V, they were unable to locate their missing Primarch, but they were able to uncover the battered shell of the Dreadnought known as the Dragon Revenant, far from intact but not yet willing to surrender to his final inevitable death. Called "The Twice-Dead" and the "Avatar of the Sacred Flames" by his brothers, Cassian Dracos returned to the battlefields of the Imperium to enact his vengeance, but he would not be as he once was. His time beneath the black, blood-soaked sands of Istvaan V had left him changed, fey and of unpredictable temper and able to exert a disturbing control over the creations of the Machine God and those bound to them. The presence of Cassian Dracos reinvigorated the demoralised crew of the Ebon Drake, and they continued their search for their missing Primarch, convinced that he yet lived.
007.M31 The Chondax Engagement Space Wolves & White Scars N/A The Alpha Legion, supposedly driven by the commands of both the Warmaster Horus and the Cabal, openly engage the White Scars in the Chondax System after years of shadowed ambushes. Their exact purpose is unclear it would seem, even to the XX Legion itself. In the wake of the engagement, the White Scars Legion learned of the Warmaster Horus' heresy when they established contact with Leman Russ on Terra in the aftermath of the Space Wolves' destruction of Prospero. Faced with the dilemma of aiding the weakened Space Wolves against a powerful force of Alpha Legion attackers, or returning to Terra as ordered by Rogal Dorn, their Primarch Jaghatai Khan chooses a third option. Seeking out answers for himself, he orders his fleet to set course for Prospero to ascertain what has truly occurred there.
007.M31 Battle of the Alaxxes Nebula Space Wolves, Dark Angels vs. Alpha Legion Pyrrhic Loyalist Victory As the Space Wolves are still licking their wounds following their heavy losses during the Fall of Prospero, they are ambushed by a sizable Alpha Legion strike force and are subsequently routed at Yarant. Primarch Leman Russ organises a tactical retreat and flees towards the Alaxxes Nebula. The Alpha Legion gives chase and soon the VI Legion finds itself in a precarious predicament -- they are effectively cut-off and surrounded. Russ reluctantly sends a distress call for assistance to his brother-Primarch Jaghatai Khan of the White Scars Legion. The Khan declines to assist the Space Wolves and instead sets course for Prospero to determine the truth for himself in regards to the Warmaster Horus' proclaimed heresy. The Space Wolves are eventually forced to flee in order to survive. A final confrontation eventually erupts between the Loyalist and Traitor forces as the Space Wolves vow to take as many of their foes with them before they are annihilated. The Sons of Russ receive relief from an unexpected quarter, in the form of the Dark Angels Legion, and their mighty Star Fort Chimaera. Answering Russ' distress signal, the combined forces of the Loyalists are able to turn the tide, and inflict serious losses on the Alpha Legion, forcing them to withdraw.
007.M31 Second Battle of Prospero White Scars vs. Death Guard Loyalist Victory After Jaghatai Khan refuses to aid Leman Russ and his battered Space Wolves fleet, he finally arrives at the ravaged world of Prospero seeking answers for himself. Teleporting down to the planet's surface with a small Honour Guard detachment, Jaghatai explores the ruins of the planet's former capital city of Tizca. During his explorations, the Primarch becomes separated, and soon finds himself trapped within a network of subterranean caverns where he is confronted by the ætherial projection of his brother, the Primarch Magnus the Red. Magnus implores his brother to choose a side and to not trust their father, the Emperor. Finding the answers he sought, Jaghatai made his way towards the surface and is reunited with his Keshig, who are soon beset by Mortarion and a contingent of Deathshroud Terminators. The Death Guard Primarch tries to persuade his brother to join the Warmaster Horus' cause, but Jhagatai refuses, and proceeds to fight his brother, gravely wounding him and forcing him to withdraw. Teleporting back aboard his flagship, the White Scars Primarch then orders his fleet to depart for Terra, having made his choice at last.
007-009.M31 Thramas Crusade Dark Angels vs. Night Lords Traitor Victory Horus orders the Traitor Primarch Konrad Curze of the Night Lords to neutralise the three Forge Worlds of Thramas, thereby denying the Loyalists a major source of war machines and materiel in the eastern Imperium. They succeed in destroying two of the region's Forge Worlds and damaging the third grievously.
007-011.M31 The Path of Heaven White Scars vs. Death Guard & Emperor's Children contingent Loyalist Trapped far from Terra the White Scars learn that the eruption of the massive Warp Storm known as the Ruinstorm in the wake of the Battle of Calth makes all long-distance Warp travel and superluminal communication impossible. Seeing no other choice, the White Scars are forced to begin a hit-and-run guerilla campaign against the Traitor Legion forces to slow their advance on the Throneworld of Terra. The White Scars proceed to lose nearly one-fifth of their fighting forces over the course of the next four solar years. As the Traitors adjusted to the V Legion's tactics, it became apparent to Jaghatai Khan that they were slowly being boxed in. Desperately, the White Scars seek out one last approach on Terra, and discover a hidden Navigator facility within the Catallus Warp Rift. Within, they find the Dark Glass artefact -- a far-less powerful prototype of the Golden Throne device, which was capable of accessing the Webway. The White Scars Stormseer Targutai Yesugai sacrificed himself when he sat upon the Dark Glass throne in order to open a temporary path through the Webway, which allowed the White Scars to escape from a massive Traitor fleet and exit the Empyrean at the outer edge of the Segmentum Solar.
004.008.M31 The Battle of Percepton Primus Word Bearers contingent & a Demi-Legio of the Legio Mortis & Legio Mordaxis vs. Ultramarines contingent Traitor Victory A large Word Bearers contingent of the 34th Company, led by Captain Sor Talgron and Dark Apostle Jarulek, assaulted the world of Percepton Primus located in the Percepton System of Ultramar at the beginning of the Shadow Crusade. They manage to cripple the defending Ultramarines fleet in 27 solar minutes, destroying nearly half the fleet, but the fight continues on the ground, as the Ultramarines stubbornly hold out for another 163 solar days, led by the Ultramarines' 17th Chapter Master Aecus Decimus. In the final desperate solar hours of the campaign, the Ultramarines utilised Phosphex, a world-killing weapon of mass destruction that their Primarch Roboute Guilliman abhorred, in order to achieve victory, though the planet was rendered a burnt cinder and uninhabitable to life. Though they were able to kill two-thirds of the Word Bearers' forces, both Talgron and Jarulek escaped the burning surface of Percepton Primus.
008.M31 The Raven Strikes Raven Guard vs. various Traitor Legion contingents Loyalist Victory The Raven Guard proceed to conduct a protracted campaign against the Traitor Legions and manage to secure multiple victories at Scarato, Kapel-5642A, Constanix II and Carandiru.
008.M31 Blood Among the Pale Stars Blackshields vs. Alpha Legion Blackshield Victory A previously unidentified group of Blackshields of unknown provenance, calling itself the Dark Brotherhood, carves out its own corsair empire on the edge of the Pale Stars and begins a long war against an Alpha Legion hunter-killer force tasked with crushing resistance to the Warmaster Horus' Dark Compliance.
008.M31 The Destruction of Bodt Loyalist Victory Iron Hands vs. World Eaters The World Eaters' fief world and Legiones Astartes training ground on Bodt is attacked by the infamous Iron-Father Autek Mor of the Iron Hands and an allied independent Loyalist force. After a savage battle, Mor is believed to have entered the subterranean macro-vaults of the city of Tredecimmia before scouring every trace of life from the surface. Bodt's supply line of Initiate recruits to the World Eaters Legion is permanently severed.
008.M31 The Burning Grave of Ohmn-Mat Mechanicum, Iron Hands vs. Dark Mechanicum, Sons of Horus Inconclusive / Mutual Annihilation The Forge World of Ohmn-Mat in the Ultima Segmentum falls into a state of civil war as its Synod Magi are split in their support for the Loyalist and Traitor causes, drawing in contingents of Sons of Horus Dark Compliance forces and Iron Hands Istvaan V survivors as the conflict escalates. Ohmn-Mat is destroyed in the conflagration and its fires still rage even in the present.
008.M31 Fall of Batzel III Space Wolves vs. Emperor's Children, Blackshields Inconclusive Space Wolves strike forces eradicate the entire 39th Millennial of the Emperor's Children during the storming of the Vykstag Winter Palace as part of the [[[Batzel III]]] Campaign for control of the Brozyn-Primaris Sector of the Segmentum Obscurus. Leaderless, Batzel succumbs to infighting and ultimately genocidal civil war. While exiting the sector, the Space Wolves strike force clashes inconclusively with an unknown and elusive Legiones Astartes force which bears no recognisable heraldry.
008.M31 The Blight of Isessos Alpha Legion vs. Planets of the Isessos System Traitor Victory A series of void raids on the outskirts of the Isessos System in the Segmentum Pacificus by an Alpha Legion strike group leads to severe casualties, which are returned to the colony habitats of the system's three Agri-Worlds for treatment. Several of the casualties are later found to have been infected with an unknown algal strain. Within a standard year this virus wipes out the system's vast macro-output saturation fields, reducing them to poisonous slime. This results in a sector-wide famine that killed an estimated ninety billion Imperial citizens and the complete political destabilisation of the region.
008.M31 The Dagonet Incident Officio Assassinorum vs. Sons of Horus Traitor Victory The hidden Departmento Assassinorum clade-masters of Terra despatch their most potent Assassins to the recently fallen world of Dagonet in an attempt to strike down the Warmaster Horus. They are unsuccessful, but from their failure Terra learns much of the new and dreadful powers of the Empyrean wielded by its foe.
008-009.M31 The Vannaheim Space Drop Iron Warriors vs. Space Wolves Traitor Victory The Iron Warriors launch a daring void assault against the orbital hives of Vannaheim, capturing vital facilities after ten solar days of brutal fighting. A Loyalist force in the Segmentum Tempestus, including isolated elements of the Space Wolves Legion, is drawn into the conflict, launching three successive counter-assaults in order to recapture the orbital hive stations' vital altitudinal control grid. Each fails to achieve its goal and countless thousands of Loyalist lives are lost. The famed Space Wolves Grand Cruiser, Helicon Spear, is captured and becomes a prize of the Iron Warriors Legion during the last, disastrous attempt.
009.M31 Battle of Perditus Dark Angels, Iron Hands contingent, Mechanicum assets vs. Death Guard contingent Loyalist Victory When the Dark Angels receive intelligence from an astropathic message from the nearby Perditus System, they act accordingly and move to intercept. Upon arrival, they interrupted the 38-solar-day-long conflict between the Iron Hands' 98th Clan-Company, led by Casalir Lorramech, and a large Death Guard contingent, commanded by First Captain Calas Typhon on the Mechanicum station of Perditus. Both sides had been fighting over an ancient sentient device, known as the Tuchulcha Engine. This device was part of a triumvirate of similar sentient devices (another being the Ouroboros and a third, unnamed engine) which when combined could create temporal rifts that bridged space and time. On its own, the Tuchulcha was capable of precise and extremely efficient Warp jumps. The matter is eventually resolved by the arrival of an overwhelming Dark Angels fleet led by Lion El'Jonson. The Lion takes Perditus under his own protection and demands the retreat of both the X Legion and the XIV. Faced with the prospect of fighting the entirety of the much larger I Legion fleet, both sides lift off from the planet's surface following the Lion's request. Wary of both sides' motives, especially First Captain Typhon's, the Lion prevented the device from falling into the Death Guard officer's hands. El'Jonson proceeded to serve his own ambitions and requisitioned the device for his personal use. The Lion ordered the destruction of Perditus, much to the consternation of both the Loyalist and Traitor commanders.
009.M31 The Tsagualsa Incident Night Lords vs. Dark Angels Loyalist Victory Forces of the Dark Angels Legion ambush the Night Lords at Tsagualsa, inflicting severe losses. Lion El'Jonson of the Dark Angels and the Night Haunter himself clash in direct contest of arms after a failed parley, and both are so grievously wounded that their warriors are forced to drag them clear of each other before the matter can be settled.
ca. 009.M31 Defence of Nagathar Dark Angels & Imperial Fists contingents vs. Word Bearers forces Loyalist Victory Severed from the main body of their Legion by the unleashing of the Ruinstorm, a strike force from the Dark Angels Legion finds shelter in the Nagathar System which had become a safe haven for several Loyalist splinter forces, the most important being drawn from the Imperial Fists. The many Loyalist factions banded together to defend Nagathar from a powerful incursion led by the Word Bearers Legion, which had hoped to prey on the system's millions of inhabitants to fuel yet another of their sorcerous Chaos rites.
009.M31 Xana Incursion Blackshields, Dark Angels contingent vs. Xana Dark Mechanicus Loyalist Victory Intelligence reaches Terra that the Renegade Forge World of Xana on the western fringe of the Imperium has reached an accord with the Traitor forces to supply the Warmaster Horus' armies with its vast output of arms and materiel. The bargain is sealed with the delivery by Xana of a number of newly created powerful Ordinatus class weapons undergoing final field tests. In what is effectively a suicide mission, a handpicked force of Legiones Astartes, including many Blackshields -- in this case Space Marines who have chosen to remain loyal despite their parent Legion's treachery -- is despatched under great secrecy to destroy the war machines and drive a wedge between Xana and the Traitors.
009.M31 Defence of Coronis Agathon 1522nd Solar Auxilia Cohort vs. Traitor sympathisers Loyalist Victory When the Parliament of Electors of the world of Coronis Agathon, captial world of the Agathean Domain, erupts into arguments over whether or not to stay loyal to the Emperor or ally with the Warmaster Horus, Ireton MaSade, the old former Lord Marshal Militant, nearly two standard centuries in age and retired from public life, and all but a recluse for nearly two solar decades, interrupts the warring chamber. Bedecked in the old livery of his Solar Auxilia regiment and flanked by troops of the Solar Auxilia Veletaris, MaSade confronts the weak-willed politicians and denounces them for their moral weakness, and declares them all Traitors to the Emperor. Before the lords of Agathon can reply or protest, the funeral guard turn their Volkite Weapons on the nobles of the Parliament and burned them to ash. Agathon and the worlds around it are placed under martial law under direct control of the "Old Guard" of the 60th Expeditionary Fleet and its direct descendants. Agathon is placed on a war footing, its people intent on having their vengeance against the Traitors.
009.M31 The Battle of Arissak Shattered Legions Forces vs. Sons of Horus Traitor Victory Having pursued the numerous attack cells made up of Iron Hands, Salamanders and Raven Guard survivors of Istvaan V, Captain Tybalt Marr of the Sons of Horus finally brings them to battle, destroying the massed fleet of Shadrak Meduson's so-called "Shattered Legions" force at Arissak.
009.M31 The Incident at Dwell Shattered Legions vs. Sons of Horus, Death Guard & Emperor's Children Inconclusive Horus arrives upon the world of Dwell, a planet settled during the Dark Age of Technology by settlers from the nearby Knight World of Molech. The Warmaster was intent upon utilising the ancient data repository on Dwell that contained information that would lead him in search of the Emperor's power. This data would lead him back to Molech, where he had unknowingly taken part in that planet's Imperial Compliance campaign solar decades earlier, before his memories had been psychically suppressed by the Emperor. Shortly after the infamous campaign on Istvaan V, the Sons of Horus were also forced to recoup their losses. Having escaped death at Arissak, one of Shadrak Meduson's surviving Shattered Legion attack cells launches a daring assassination attempt on Horus at Dwell. With his brother-Primarchs Fulgrim and Mortarion at his side, Horus prevails, but having had the true threat revealed to him, he grants Tybalt Marr permission to take any action he deems appropriate to eradicate the so-called "Shattered Legions."
009.M31 Battle of Molech Sons of Horus, Death Guard vs. Blood Angels detachment, Loyalist & Traitor Imperial Knight Houses, Imperial Army Traitor Victory Horus leads both the Sons of Horus and the Death Guard Legions in the invasion of the Fortress World of Molech. Having recovered some of his memories in regards to the earlier campaign that took place solar decades earlier, Horus uncovers the truth about the hidden subterranean Warp portal that leads into the Realm of Chaos and that the Emperor used millennia before to gain much of his secret knowledge and power. Wanting this power for himself, Horus launches a massive strike on the unsuspecting world. During the height of the conflict, the Knight House Devine turns against the Imperium and joins the invading forces, betraying the defenders to their deaths. A force of the elite Knights-Errant, a secretly founded order of Loyalist agents, are despatched to Molech by Malcador the Sigillite to prepare the way for a direct assault by the Space Wolves against the Warmaster's flagship. Having recently won the full blessings of the Ruinous Powers, Horus is undefeatable and only a handful of Knights-Errant, including Garviel Loken, manage to escape to bring news of the Warmaster's redoubled strength back to Terra.
009.M31 The Sangraal Campaign and the Salvation Run Imperial Fists vs. Traitor Dark Mechanicum Loyalist Victory A hand-picked Imperial Fists assault force despatched from Terra launches a daring raid to capture the antidote to a slow-burning Exterminatus-class viral weapon deployed against the Loyalist holdfast of Gramercie on the contested Hive World of Herkaliaum. After recovering the antidote stocks from the Traitor Mechanicum-Biologis gene-labs, the heavily outnumbered Imperial Fists then fight their way through massed Traitor forces, running a deadly gantlet through the underhives of Herkaliaum to deliver the antidote to Loyalist medicae detachments, thus saving the population of the Gramercie sub-hive. Viral overspill ravages the Traitor forces now unable to contain or cure the contagion in their own ranks, and within solar weeks, Herkaliaum is liberated. The legend of the "Salvation Run" becomes a rallying cry for Loyalist support in the sector, turning the Sangraal Campaign in the Loyalists' favour and cementing their hold on the loyalty of the Segmentum Solar.
009.M31 The Establishment of the Imperium Secundus Ultramarines, Dark Angels, Blood Angels, Space Wolves (Detachment sent to observe Primarchs, Shattered Legions elements comprised of Iron Hands, Raven Guard, Salamanders, as well as elements of the Imperial Fists & White Scars N/A With the Imperium severed in two halves, isolated and ignorant of each other as a result of the raging tumult of the Ruinstorm, the light of the Astronomican is no longer visible from Ultramar and no word of the Emperor has been heard for several standard years. Ultramarines Primarch Roboute Guilliman declares the foundation of the "Imperium Secundus" as a means of continuing the fight against the Traitors and securing the Emperor's great work. When the Blood Angels arrive at Ultramar having escaped the Signus Cluster, Guilliman proclaims Sanguinius as the rightful heir to the Emperor and the Imperator Regis or Regent of the Imperium Secundus. [Extract sanctioned for data purge]
009.M31 Battle of Sotha Night Lords vs. Ultramarines Pyrrhic Loyalist Victory The far-flung world of Sotha lay close to the edge of the galaxy's Eastern Fringe, almost at the limits of both the fiefdom of the Five Hundred Worlds of Ultramar and the span of all Imperial territory. On this world the Ultramarines had discovered beneath its tallest peak, Mount Pharos, a massive aperture constructed by an unknown xenos species. This device functioned both as a telepathic beacon and route-finder, and it also permitted instantaneous communication across unimaginable distances, even penetrating the raging tumult of the Ruinstorm. Following their defeat at the hands of the Dark Angels at Tsagualsa, remnants of the Night Lords Legion followed this beacon in the Warp, which guided them safely to the world of Sotha. Over many solar months, the Night Lords secretly gather intelligence on the suspicious activities of the Ultramarines, and soon discover the nature of the arcane device, also named the Pharos, upon the restricted planet. The Night Lords launched a surprise assault upon the lightly-garrisoned world, intent on seizing the Pharos in order to use it to determine the location of their flagship, the Nightfall, as well as the whereabouts of their missing Primarch Konrad Curze. In the ensuing battle, the Loyalist Iron Warriors Warsmith Barabas Dantioch sacrifices himself by overloading the Pharos and burning it out, so that the Night Lords will be unable to utilise the device's powerful abilities. What far-reaching consequences this will have for the galaxy will not come to pass for another ten standard millennia, for the massive final emission of energy by the Pharos through the Warp penetrated the intergalactic void and served as a beacon one last time -- for the Hive Fleets of the Tyranids.
ca. 009.M31 Vulkan Lives Primarch Vulkan, Dark Angels, Blood Angels vs. Primarch Konrad Curze Inconclusive Vulkan's charred remains are recovered by the Ultramarines, who initially assumed the massive corpse was some kind of grotesque statue. But over the following solar days, Vulkan's body begins to regenerate, and eventually life returns to it. Vulkan returned to life in a mentally unstable state, and was often violent and incoherent. This was due to the perverse bond that had formed between Vulkan and Konrad Curze during the solar months he had been continuously tortured by the Night Haunter while a prisoner aboard the Night Lords' flagship Nightfall. Vulkan often reacted violently as he could sense the presence of Curze nearby. Unknown to the Dark Angels, who had recently arrived on Macragge, Curze had actually accompanied them, taking refuge in the bowels of their flagship following the Night Lords' defeat at Tsagualsa. As the Night Haunter proceeded to cause as much murder and chaos as possible among the people of Macragge, Vulkan eventually broke his bonds and began hunting the Night Haunter. They battled across Macragge's capital city until they were confronted by the Perpetual John Grammaticus, who used the Fulgurite, a petrified piece of the Emperor's psychic power, and stabbed Vulkan through the heart, seemingly killing him. This time, however, Vulkan did not recover from the wound. In the battle's aftermath, Curze escaped. Vulkan was laid in stasis within a stasis-sarcophagus, hand-crafted by Guilliman himself, with the words "Unbound Flame" engraved on its side.
ca. 009.M31 Rebirth of Vulkan Salamanders vs. Death Guard & Word Bearers contingents Loyalist Victory Following the death of their Primarch, the Salamanders Shattered Legion survivors of Istvaan V had also been drawn to Macragge by the empathic beacon of the Pharos and were allowed to stand vigil over their fallen Primarh's casket. Their surviving First Captain Artellus Numeon was convinced that Vulkan yet lived, and eventually took his Primarch's body on an arduous expedition back to Nocturne. He was certain that if Vulkan's body were lowered into the cleansing fire of the Unbound Flame of Mount Deathfire, he would be restored to life once again. The Salamanders vessel was pursued by a large Traitor fleet consisting of elements of both the Death Guard and the Word Bearers, whose commanders each had their own personal reasons for acquiring Vulkan's body. Miraculously, the Salamanders unexpectedly found their way through the turbulent Ruinstorm, and arrived at their homeworld of Nocturne, where they were greeted by Nomus Rhy'tan, the Lord Chaplain of the XVIII Legion and Keeper of the Keys of Prometheus. A battle ensued between the Traitor and Loyalist forces, in which the Salamanders eventually emerged victorious. Following this victory, the Salamanders conducted the burial rites of Vulkan, and returned their Primarch's body to the fires of Mount Deathfire, in the hopes that Vulkan would be resurrected. After over a solar week of waiting, the uncertainty broke Numeon's spirit. As the next Time of Trials drew near, Numeon renounced his rank and position. He wandered away into the burning ash wastes around Mount Deathfire and offered himself as a final sacrifice so that his father and Primarch could be restored.
009-053.M31 The Carnage of Morox Loyalist vs. Traitor-aligned Imperialis Auxilia & Imperialis Militia forces Inconclusive In one of the largest confrontations between Loyalist and Traitor-aligned mortal auxilia and militia forces, in excess of three billion battlefield fatalities are recorded as the death toll from a grinding war of attrition on the sector capital world of Morox Excellus. The Morox Civil War takes place in almost total isolation from the rest of the galaxy owing to turbulent Warp Storm activity and the lack of any real strategic significance to either side of the wider conflict, and is noted for the exponentially increasing levels of atrocity and rapid technological regression of the conflict.
010-015.M31 The Solar War Traitor Legions & Dark Mechanicum vs. Loyalist forces Loyalist Victory The battle for the Sol System, known as the Solar War and long threatened, begins as Traitor infiltration forces and probing raids from without, and Dark Mechanicum attacks and attempted break-outs from besieged Traitor-controlled Mars test the defences of the Throneworld of humanity. Conflict within the system is not concluded until the eventual lifting of the Siege of Terra. {See Extrapolation Addenda CVX-CVXVIII-Classified Amaranth-Gold}
  • 010.M31 The Drussen Atrocity - Rumours of the presence of a forbidden Empyreal engine draws the attention of splinter elements of both Traitor and Loyalist forces, leading to a brief war which ravages the isolated world of Drussen, the apocalpytic conflict halving the world's population in a single night.
010.M31 The Scouring of Gilden's Star Blood Angels vs. Word Bearers Loyalist Victory Scattered elements of the Blood Angels Legion fight a long and bloody campaign against Word Bearers forces near the galactic core on the borders of Imperium Secundus that culminates in the near-total destruction of both armies. During the campaign, the Blood Angels prove merciless in scouring worlds which have embraced the daemonic teaching of the "Dark Apostles" of the Word Bearers, putting all seven colonised worlds of Gilden's Star to the sword in one particularly notable instance.
010.M31 The Battle of Nycron Salamanders, Imperialis Auxilia, Legio Astorum vs. Emperor's Children, Legio Mortis Loyalist Victory Under the direction of Imperial Fists Primarch Rogal Dorn, a Loyalist battlegroup led by elements of the Salamanders Legion, and supported by thirty regiments of the Imperialis Auxilia and a strike force of Legio Astorum Titans, engage an Emperor's Children millennial assigned to garrison the Beta-Garmon System on the edge of the Segmentum Solar. The Emperor's Children contingent is surprised at Nycron City on Beta-Garmon II and after a hard-fought battle, the Emperor's Children forces along with their Legio Mortis allies at Beta-Garmon III are driven out, placing the system into Loyalist hands and triggering within the standard year the first of an escalating series of Traitor counterattacks with the goal of retaking Beta-Garmon as a stepping stone for an eventual attack on Terra. Ultimately, these will only serve as a prelude to the far greater conflict in the system to come.
010-011.M31 Battle of Tallarn Iron Warriors vs. Misc. Imperial Army Regiments, various Space Marine Legions (including elements of the Imperial Fists, Iron Hands, and White Scars), & Legio Gryphonicus Pyrrhic Imperial Victory Tallarn, an Imperial muster world of almost unparalleled size and importance, comes under direct attack by the Iron Warriors Legion after their emergence from the Eye of Terror in an attempt by Perturabo to retrieve a powerful Chaos artefact hidden beneath the planet's surface. Here the Traitors unleash a Life-Eater virus bombardment that renders the surface of the once-verdant world of Tallarn poisoned slime and makes the air unbreathable. The Traitor invasion that follows develops into the largest armoured battle of the Imperium's history, a war fought under the most hellish conditions imaginable. As the war grinds on, it draws in Loyalist and Traitor forces from hundreds of worlds across the entire Segmentum Tempestus before its cataclysmic conclusion and the subsequent retreat of the Traitor forces.
010-012.M31 Fate of the Sabalis Liberatus Shattered Legions forces N/A The Sabalis Liberatus, a Raven Guard Legion battlecruiser lost in the Warp since escaping the void battle over Istvaan V, finally breaks into realspace near Galaspar on the borders of the Veiled Region on the southern galactic fringe. The survivors on board, comprising a mixture of Loyalist Legions, have spent the time in self-imposed suspended animation and awoke to find themselves utterly cut off from information or support. Fired on by Imperial patrol vessels whose captains have sided with the Traitors, this "Shattered Legion" force boards the patrol vessels and conquer their attackers. Effecting repairs from the captured voidships, they begin a further two-year odyssey of battle to return them to the Segmentum Solar and finally Terra, where they will ultimately fight in the void battles against the Traitor onslaught in the closing days of the great civil war.
010.M31 The Dispute of Iron Begins Loyalist Forge Worlds vs. Traitor Forge Worlds Inconclusive Across the sectors of the Segmentum Tempestus and Segmentum Pacificus are located numerous Forge Worlds known collectively as the Belt of Iron. Since the sundering of the Imperium, many of their number have declared for the Traitor cause at the engineering of the Fabricator-General of Mars, while others have remained loyal to Terra or in some cases sought to remain aloof from the conflict as much as possible. Strife and tentative conflict between these once-aligned worlds erupts finally into full-scale war in 010.M31, which pitches the Mars-aligned Forge Words of Incunabula, Urdesh, Valia-Maximal and Kalibrax against the forces of Loyalist Forge Worlds Graia, Arl'yeth and Atar-Median, while Arachnis and Jerulas Station both fall into the anarchy of civil war. The resulting conflict, later known as the Dispute of Iron, sees the forge lords, their armies and allied Titan Legions and Knight Households turn on each other in protracted warfare, with scores of human-inhabited worlds in the region suffering as they become the battlegrounds upon which the forge lords fight.
010.M31 Battle of Pluto Imperial Fists vs. Alpha Legion Loyalist Victory The Alpha Legion carries out multiple diversionary attacks of sabotage and preparation, which plunges the Sol System into complete chaos. Their true target, however, is the fortress moon of Hydra, which orbits Pluto. First Captain Sigismund and a small fleet of Imperial Fists stubbornly defend Pluto against the larger Alpha Legion fleet until help arrives, in the form of the great mobile star fort Phalanx and a large fleet of Imperial Fists and Armada Imperialis warships. At the height of the battle, Lord Rogal Dorn leads an assault on the fortress moon and confronts his brother Primarch Alpharius and engaged him in melee combat. Alpharius is killed by Dorn, and the Alpha Legion forces are forced to withdraw.
011.M31 The Malagant Conflict Raven Guard & Imperialis Auxilia vs. Death Guard Loyalist Victory While the surviving Loyalist enclaves have been apparently crippled by the Warmaster Horus' onslaught, those Death Guard elements assigned to the garrison of Barbarus spearhead an assault into the southern reaches of the Imperium. The grim warriors of Barbarus made the vast industrial hives of Malagant their prime target, a world made valuable by the strategic worth of its manufactoria, and to crush the defiance of the surrounding sectors, many of whom looked to the determined Loyalist leaders of Malagant for leadership. Yet where the Death Guard had expected to crush the mortal Malagantine auxilia in short order, they found themselves mired in cunning ambushes and punishing counterattacks led by Legiones Astartes bearing the sable mark of the Raven Guard. Lacking the numbers to meet the Traitors head-on, the sons of Corax plied their deadly skills as skirmishers and assassins upon their erstwhile brothers; trapping them on a world they could not afford to abandon, battling a foe they could not pin down and crush. For three standard years, little more than a company of Raven Guard occupied an augmented Chapter of Barbarus' finest, until 014.M31 when the Death Guard retreated in the face of approaching Loyalist reinforcements from Inwit.
011.M31 Battle of Zepath Dark Angels & Solar Auxilia forces vs. Word Bearers & World Eaters forces Loyalist Victory Obsessed with hunting down the Night Haunter, Lion El'Johnson eventually is able to trace a slim lead on his former brother's whereabouts to the Zepath System, which had since fallen to the Word Bearers and World Eaters forces. Farith Redloss, the Lieutenant-elect of the Dark Angels' Hexagrammaton Dreadwing formation, was charged with leading the hunt for Konrad Curze upon the world of Zepath. The Dark Angels quickly uncovered the horrors perpetrated by the Word Bearers to fuel their dark Chaos rituals. Eventually, the Dark Angels took part in multiple engagements against the forces of both Traitor Legions, which culminated in the Zepathian capital city of Numentis. The Traitor forces were utterly annihilated by the victorious Dark Angels. The world was left in the care of its surviving population.
011.M31 Scouring of Nostramo Sector Blackshield Forces (Ashen Claws) vs. Night Lords remnant forces Blackshield Victory In 017.M31, after the end of the Heresy, a Retribution Fleet designated Battlefleet Vengeance, led by the Blood Angels' 33rd Company, 9th Chapter, launched a campaign into the Nostramo Sector for further vengeance in their Lord Sanguinius' name, against remaining active Night Lords combat units within the sector. Yet despite all intelligence to the contrary, no determined resistance was to be encountered by these fleets. Of the VIII Legion, only scattered and isolated warbands were discovered, and none larger than a reinforced company. They soon uncovered, on multiple, formerly Night Lords-held worlds, evidence that an unknown Blackshield force had ravaged the Nostramo Sector in 011.M31, leaving nothing but ruined fortresses and drifting battle-scarred wrecks of the VIII Legion in their wake. It wouldn't be until 017.M31 that this mysterious Blackshield force would be identified as the mysterious Ashen Claws.
013.M31 A Return to Honour Ultramarines vs. Word Bearers Pyrrhic Imperial Victory Arcaes Odenathus, a Captain-Praetor of the Ultramarines 10th Chapter, rallied the scattered survivors of his own brethren and those other Loyalists fighting across the Dominion of Storms in the galactic northeast and lead them to the world of Honourum. Unexpected and unlooked for, this Loyalist assault strikes the Word Bearers garrison like a thunderbolt. Three solar weeks of desperate fighting ensues, and as all the Word Bearers' urgent requests for reinforcements are ignored by the Warmaster Horus, focused now on his final push toward Terra, the sons of Lorgar resort to the most heinous of tactics to defend themselves. Daemons, Warp-tainted infiltrators and terrors of the wars of Old Night are unleashed, with both sides driven on past mortal endurance by their mutual hatred. When the last Traitor finally fell, there was nothing left of the grand cities of Honourum but blasted ruins; ruins whose very substance was so contaminated by the fell powers and terrible weapons they unleashed that they would blight Honourum longer than the memory of the wars which spawned them.
014.M31 Siege of Terra (Battle of Terra) Traitor Legions, Dark Mechanicum, Traitor Legio Titanicus Legions, Imperialis Auxilia & Imperialis Militia & Chaos Cult elements vs. Blood Angels, Imperial Fists, White Scars, Mechanicum, Loyalist Imperialis Auxilia & Imperialis Militia, as well as various Loyalist Legio Titanicus Legions Pyrrhic Loyalist Victory The Siege of Terra, also called the Battle of Terra, is the final epic and cataclysmic campaign of the Horus Heresy. Many of the Loyalist Legiones Astartes had been waylaid by the forces of the Traitor Legions loyal to the Warmaster Horus and were unable to make their way towards Terra. The Imperial Fists had already returned to the cradle of humanity and under the stern gaze of their Primarch Rogal Dorn had adequately prepared Terra's defences as best they could. Jaghatai Khan, of the White Scars Legion, had also managed to make his way to Terra with his Legion to help with the defence of the Imperial Palace. The Blood Angels Legion was also able to make the Warp jump to Terra in time to meet the oncoming Traitor assault. Three entire Titan Legions of the Mechanicum and close to 2 million mortal soldiers of the Imperialis Auxilia stood alongside the Loyalist Astartes to face the hosts of Chaos in a battle that would determine the fate of Mankind for the next ten millennia. Yet for all the might of the Emperor, for every effort of Sanguinius and the remaining Loyalist Primarchs, the forces of Horus drove all before them. In too short a time, the Emperor of Mankind was assailed within His great palace on Terra. The Siege of Terra following the initial assault on the Imperial Palace lasted for fifty-five solar days. Both sides knew that victory or defeat for the Imperium of Man was at hand. Inexplicably, the Warmaster lowered his Void Shields aboard his flagship, the Vengeful Spirit in the final hours of the siege, and the Emperor rose to the challenge. With Sanguinius and Rogal Dorn at His side, along with a detachment of Legiones Astartes from both Legions, as well as the Emperor's personal guardians, the Legio Custodes, the Emperor teleported aboard the infamous Traitor flagship. Once the Loyalists were aboard the flagship, they were all separated before they rematerialised by the Warmaster's fell powers and scattered throughout the massive warship. It was the Emperor who first arrived to the bloody scene in the Warmaster's throne room -- for the winged corpse of the angelic Sanguinius lay at Horus' feet. Father and son fought one another in a titanic struggle, the fate of all humanity hanging in the balance. In the end, the Emperor slew his once-beloved son and used his immense psychic powers to eradicate his soul from the Warp so that he not be resurrected by the Ruinous Powers he served. But the Emperor had been mortally wounded himself during the vicious fighting. With their leader gone, the Traitor Legions were routed from Terra and chased by the vengeful Loyalist forces into the hellish realm of the Eye of Terror, while the Emperor was ultimately saved by the arrival of Rogal Dorn, who took his dying father back to the Imperial Palace. Upon the Emperor's final instructions, Dorn had Him placed into the confines of the life-sustaining mechanisms of the great arcane device known as the Golden Throne, and then He spoke no more. Humanity had prevailed, and the Imperium of Man would live to endure, but had paid a terrible price for its victory -- a price that would continue to be paid by the generations to come for the next 10 millennia.

Immediate Post-Heresy Chronology

Included below are events that took place following the immediate end of the Horus Heresy, many of which directly (or indirectly) were affected by the final campaigns of the galaxy-wide civil conflict that ravaged thousands of worlds and cost hundreds of billions of lives.

Participating Force(s)
ca. 014.M31 The Fall of Caliban Dark Angels vs. Fallen Angels Pyrrhic (Caliban destroyed) In the aftermath of the Horus Heresy, the surviving Loyalists rallied the reeling Imperium. The Dark Angels took a significant part in these battles, which later came to be called the Great Scouring. As they pursued the rebels, the I Legion diverted to nearby Caliban, which had been enshrouded by Warp Storms since Horus' betrayal. For Lion El'Jonson, one final act of treachery remained to be discovered. Upon the Dark Angels' arrival in orbit, they were fired upon from the surface. Pulling back the Legion fleet, El'Jonson tried to find out what had happened, and discovered that his second-in-command Luther -- who had become embittered by what he perceived as El'Jonson always taking all the glory -- had poisoned the minds of the Dark Angels garrison and the new recruits that had been left on the planet against their Primarch. In the ensuing conflagration, the Dark Angels unleashed a vicious orbital bombardment on the planet's surface while the Lion confronted Luther in personal combat. The Lion is mortally wounded, while Caliban was torn apart by the unleashed forces of the Ruinous Powers. Only their fortress-monastery, the Angelicasta, survived the destruction of Caliban. Luther is taken into custody and imprisoned, while The Lion's body is nowhere to be found.
ca. 014-021.M31 Great Scouring Loyalist Legiones Astartes vs. Traitor Legions Loyalist Victory The forces of the Imperium launch a great counteroffensive against the Traitor Legions of the slain Warmaster Horus, following the end of his lamentable civil war during the Battle of Terra. Before actually being confined within the life support mechanisms of the Golden Throne, the Emperor had pronounced judgment on the Traitors: declared Excommunicate Traitoris, they were to be driven into the hellish region of the Warp rift called the Eye of Terror, which would hold them for all eternity. All records and memory of the Traitor Legions were to be expunged from the Imperial archives. Worlds such as Istvaan V and Davin were scoured clean of all life because of their corruption by Chaos. The Traitor Legions' associated troops from the Dark Mechanicum or the regiments and starships of the Imperial Army and Armada Imperialis that had turned to Chaos were to be destroyed or driven into the Eye. It would be as if the Traitor Legions had never existed to sully the Imperium with their betrayal. The fighting of this campaign would continue for another seven standard years after the end of the Heresy. The Loyalist Space Marine Legions destroyed at the Drop Site Massacre on Istvaan V were slowly reestablished using what little gene-seed the survivors had managed to escape with, though the Legions were refashioned as 1,000-Astartes Space Marine Chapters rather than full Legions as Primarch Roboute Guilliman's Codex Astartes now required after the Second Founding at the dawn of the 32nd Millennium.
Unknown Date.M31 Battle of Eskrador Ultramarines vs. Alpha Legion Loyalist Victory After the death of Horus at the end of the Horus Heresy during the Great Scouring, the Alpha Legion and the Ultramarines Legion met in battle on the world of Eskrador, where Roboute Guilliman faced his hated brother Primarch Alpharius (unaware that it was actually Alpharius' twin brother Omegon, who had assumed his brother's identity following Alpharius' death at the hands of Rogal Dorn during the Battle of Pluto) in bitterly contested close combat. Both struck one another in an instant, each Power Sword making a single stroke. For a solar second the two Primarchs stood facing one another, than Alpharius slumped to the ground. Exalted by their Primarch's victory, the Ultramarines renewed their attack and cut down every last Alpha Legionary. But their exaltation was short-lived, as over the next few solar days the Ultramarines were harried from all sides by the Eskandor natives as well as remnants of Alpha Legionaries hiding throughout the mountains. After another solar week of futile combat against their shadowy opponents, Guilliman ordered his Ultramarines to evacuate the planet's surface. He then used his Legion's voidships to bombard the Traitors from orbit. Despite Guilliman's protests that he had no wish to fight such dishonourable foes, it seems hard to dispute the fact that the Ultramarines were soundly beaten by the Alpha Legion at every turn, despite the loss of Alpharius.
Unknown Date.M31 The Iron Cage Imperial Fists & Ultramarines vs. Iron Warriors Inconclusive The Iron Cage is the name given to the greatest battle fought between the Imperial Fists Legion and their hated rivals, the Chaos Space Marines of the Iron Warriors Traitor Legion, on the world of Sebastus IV. The battle was fought during the years immediately following the end of the Horus Heresy. The Imperial Fists assaulted the planet after its defences had already been prepared by the Iron Warriors, who had nicknamed their network of fortresses and defensive positions "the Eternal Fortress." Dorn vowed he would "Dig Perturabo out of his hole and bring him back to Terra in an iron cage." The Imperial Fists fell into the trap and suffered heavy casualties before the Iron Warriors were driven off-planet only due to the intervention of the Ultramarines Legion. The battle should have favoured the Traitors, but the Imperial Fists refused to die. When their ammunition ran out, they fought hand-to-hand, and the trenches of the Eternal Fortress ran with blood. Had Roboute Guilliman and his Ultramarines Legion not intervened, the two Legions would likely have annihilated each other, and to this day, their mutual hatred persists. The experience of the Iron Cage proved painful for the Imperial Fists but was also important in forging the modern character of the Imperial Fists and their Successor Chapters.
Unknown Date.M31 Eastern Fringe Genocide Night Lords vs. Loyalist forces Traitor Victory Following the death of Horus during the Battle of Terra, the Traitor Legions were driven into the Eye of Terror. Unlike the other Traitor Legions, after their defeat in the Thramas Crusade, the Night Lords did not splinter into separate warbands and flee like the rest of their fellow Traitors. Instead, the Night Lords conducted a massive campaign of genocide and terror against the Imperium across the Eastern Fringe of the galaxy, the likes of which has never been seen before, or since. The Legion betrayed the growth of the increasing sense of self-destruction which drives its Astartes, much as it drove their Primarch. The Night Lords' rampage is only stopped by the assassination of Konrad Curze at the hands of the Callidus Assassin M'Shen on Tsagualsa.
Unknown Date.M31 Battle of Skalathrax World Eaters vs. Emperor's Children N/A On the Daemon World of Skalathrax, deep in the Eye of Terror, shortly after the Horus Heresy, the World Eaters and the Emperor's Children fought. Amid the World Eaters was the Champion of Khorne named Khârn. After a full day of vicious fighting in what would become known as the infamous Battle of Skalathrax, the terribly frigid Skalathrax night began. Horrified, Emperor's Children and World Eaters Traitor Marines alike ran to their shelters, for the freezing night would kill even a Chaos Space Marine in a matter of moments. Khârn raged over being delayed from slaughter for even a single night. Filled with anger when he saw that his brother Traitor Marines were creeping back to the shelters, he took up a Flamer and burned them down, slaying with his Chainaxe Gorechild any who tried to stop him. The night was filled with the screams of the dying and the freezing as Khârn strode the streets of the dead city of black stone, killing Emperor's Children and World Eaters alike, burning any shelters he found. The night was lit by flames as the Emperor's Children and the World Eaters fought each other and themselves for the few remaining shelters. By morning, most of the World Eaters were dead, the survivors split into small warbands, the shattered remnants of the once great companies of the XII Legion. The World Eaters Legion would never reunite and would remain scattered in multiple Chaos Space Marine warbands for the next ten millennia.
Unknown Date.M31 First Battle of Garm Space Wolves vs. Thousand Sons Loyalist Victory In the aftermath of the Horus Heresy, the Thousand Sons attacked the Space Wolves' Shrine World of Garm, which was named for a famous Wolf Lord from the earliest days of the Space Wolves Legion who had given his life defending their Primarch Leman Russ from an attack by Magnus the Red. Leman Russ raised a cairn to Garm upon the place of his death and placed the Spear of Russ, the mighty weapon gifted to him by the Emperor Himself which had wounded the Traitor Magnus, atop Garm's tomb. The Space Wolves were able to fight off the Thousand Sons Traitor Legion and drive them from the world.
675.017.M31 Shadows of the Past Blood Angels contingent & Rogue Trader Skathe N/A A Blood Angels Retribution Fleet of the 33rd Company, 9th Chapter, enters the Nostramo System and began an investigation of the moon of Tenebor, which formerly orbited the destroyed Night Lords homeworld of Nostramo. Amidst their investigation, they discovered that the expected reinforced void station was a lifeless and gutted corpse, indicating it had fallen to some unknown misfortune. It was later determined from the garrison's damaged data cores that it had been attacked by an unknown Blackshield force. They had engaged and destroyed the defending Night Lords garrison, leaving behind well over 1,000 mortal auxiliary troops and some 300 Night Lords, before disappearing. Upon the Hive World of Cairn, Rogue Trader Erasmus Skathe, who had arrived in the sector seeking salvage, found evidence of an unknown force of Legiones Astartes warriors bearing many similarities to those who struck Tenebor. This now Dead World had been inhabited by degenerate humans, and further evidence showed that this same unknown force had trapped its inhabitants in the darkened sub-levels of its hive cities, sealed them in, and left them to die.
017.M31 The Chronicle of Ashes Ultramarines contingent vs. Word Bearers contingent Loyalist Victory A task force of the Ultramarines Legion, composed of the survivors of the 19th, 48th and 207th Destroyer Cadres, encountered several Renegade Word Bearers Cruisers defending a lone Gloriana-class Battleship identified as the Chronicle of Ashes in the wild and uncharted space of the Dominion of Storms. Overwhelming the Traitor Escort craft, the Ultramarines captured the Chronicle of Ashes in a furious boarding action involving nearly three hundred Astartes and two full solar days of bloody close quarters fighting as they swept the ship's innumerable decks clear of Traitor Space Marines. In the aftermath of their victory, the Ultramarines discovered something unexpected in the vaulted halls of the Chronicle of Ashes' upper decks -- an account written in the twisted and fey language of now-dead Colchis, the Word Bearers' homeworld, which revealed a wealth of information regarding events previously hidden to Imperial scholars. This vessel was later cleansed and re-dedicated as the Lex Talonis, before being presented to the Ultramarines in 022.M31 and incorporated into the newly-founded Nemesis Chapter.
ca. 019.M31 Third Battle of Paramar Loyalist Forces vs. Traitor Legion forces Loyalist Victory Following the conquest of the vitally-important Forge World of Paramar V, the Warmaster Horus was forced to divert additional forces to Paramar to hold the system, forces which he had desired to use elsewhere, as having gained this great prize he could not afford for his enemies to regain it. This fear would be proved accurate as the system would see an attempted Loyalist counterinvasion two standard years later in 008.M31, and further catastrophic warfare during the dark years of the Great Scouring in 019.M31 as the Loyalists sought to reclaim the system once and for all.
033.020.M31 Reclamation of the Shroud of Eventide Blood Angels contingent N/A A Blood Angels Reclamation Task Force, consisting of the 9th Chapter, Angels Vermillion, travels to the Nostramo System in order to salvage a Space Hulk designated the Crimson Intent, which was formerly known as the Night Lords' vessel Shroud of Eventide. The Blood Angels successfully salvage the mighty vessel and cleanse and re-dedicate it, so that it may serve the sons of Sanguinius that yet remain with honour. They also retrieve information from the hulk's damaged data cores in regards to the vessel's last battle, which was fought with a mysterious Legiones Astartes Blackshield force that engaged them.
ca. 021.M31 Completion of the Codex Astartes Primarch Roboute Guilliman N/A The Ultramarines Primarch Roboute Guilliman completes his magnum opus, the Codex Astartes, a volume which lays down the new organizational and tactical doctrines for existing and future Loyalist Space Marine Chapters. The Loyalist Legiones Astartes destroyed at the Drop Site Massacre on Istvaan V were slowly reestablished using what little gene-seed the survivors had managed to escape with at this time, though the Legions were refashioned as 1,000-Astartes Space Marine Chapters rather than as full Legions. Guilliman's Codex Astartes now required this after the Second Founding at the dawning of the 32nd Millennium, so that no single individual could ever again corrupt or wield the awesome power of a full Astartes Legion of old.
021.M31 The Second Founding Dark Angels, White Scars, Space Wolves, Imperial Fists, Blood Angels, Iron Hands, Ultramarines, Salamanders, Raven Guard and their Successor Chapters N/A The remaining Loyalist Legiones Astartes are broken down into a smaller existing formation, known as a Chapter, comprised of only 1,000 warriors. This ensures that one man would never again command the full might of an entire Legion of Astartes. Twenty-three new Space Marine Chapters are created in this manner, whilst the 9 existing Loyalist Legions are reshaped into smaller Chapters that continue to bear the original names of their Legions. The Grey Knights, a special Space Marine Chapter comprised entirely of psykers that will eventually evolve into the Chamber Militant of the Ordo Malleus of the Inquisition, had been secretly created by Malcador the Sigillite, the Regent of Terra and chief aide of the Emperor before his death, on the moon of Saturn called Titan during the Heresy. This newly formed Chapter serves as the eventual headquarters for the Ordo Malleus, the branch of the Inquisition dedicated to protecting the people of the Imperium from the daemonic forces and temptations of Chaos. The newborn Inquisition takes as its eventual symbol Malcador's own original personal sigil in his memory.
ca. 022.M31 Departure of the Raven Lord Primarch Corvus Corax N/A After the Heresy, Corvus Corax personally gave the Emperor's Peace to every surviving aberrant Astartes that had resulted from the Raven Guard's accelerated program of Space Marine development, an act that led him to lock himself in his personal chambers in the Ravenspire on Deliverance and beg the recently-ascended Emperor for forgiveness. Unable to alleviate his guilt, the Primarch left the Ravenspire exactly a standard year after he first went into seclusion in a transport that was headed for the Eye of Terror. Corax's fate remains unknown to this day. His last recorded words as he departed Deliverance were, 'Nevermore'.
ca. 022-Unknown Date.M31 The Scourge of Dynat Crowbane Alpha Legion contingent Traitor Victory Driven outwards by the resurgent armies of the Emperor of Mankind after the Battle of Terra in what was later called the Great Scouring, Dynat Mal of the Alpha Legion, the main architect behind the Raven Guard's shaming defeat at the Battle of Lyx, took his forces to the Dark Marches region of the Segmentum Tempestus. There he raided and destroyed the major outpost on Amarah Prime and gathered a coterie of Renegades, mutants and Heretics that took the name of "The Shadowed Ones". Hiding out with his fleet in the debris fields and nebulas of what would one day become the Orpheus Sector, Dynat Mal successfully ambushed and destroyed several Imperial punitive expeditions and established a reign of terror that lasted for several decades. Although the fate of the Shadowed Ones remains a mysterious one, it is generally believed that Dynat Mal was defeated and subsequently killed by an awakened force of Necrons belonging to the Maynarkh Dynasty.
ca. 032.M31 Castigation of Colchis Ultramarines vs. Word Bearers contingent, Imperialis Auxilia & Population of Colchis Loyalist Victory Following the end of the Horus Heresy, the Imperium of Man launched a retribution crusade, known as the Great Scouring, to drive out the remaining Traitor Legions and those forces still loyal to them. Following this period of bloody vengeance and violence, around 032.M31, the Ultramarines were finally able to take the fight to Colchis in retribution for what the Word Bearers had done to Calth during the early years of the Horus Heresy. When they arrived, they found a devastated world, its industry in ruins and its people clinging desperately to civilisation. Given Lorgar's treachery and the Imperium's fear that his Chaotic taint had spread throughout the population who had converted to the Word Bearers' heretical faith in the Ruinous Powers, the newly-formed Inquisition ordered the planet to undergo Exterminatus. The Ultramarines' Battle Barge Octavius bombarded Colchis with Cyclonic Torpedoes. The geological structure of Colchis was highly unstable and the resultant seismic activity caused by the torpedoes' detonations split the planet apart. Nothing now remains of Colchis and its location is still a closely-guarded secret of the Inquisition.
ca. 084.M31 Disappearance of The Khagan White Scars contingent vs. Dark Eldar N/A While traveling into a region of space known as the Maelstrom, a large Warp rift in the Ultima Segmentum that is a somewhat smaller counterpart of the Eye of Terror, the Primarch of the White Scars, Jaghatai Khan, disappeared. It is believed that the Khagan was in pursuit of the Dark Eldar who had savaged Mundus Planus following the Battle of Corusil V with his 1st Brotherhood when he went through a Warp Gate into the Dark Eldar portion of the Webway, ultimately vanishing forever. None can say what befell the Primarch -- if he was lost in the Warp or if he was slain or captured at the hands of an alien warlord -- but the White Scars believe he still hunts across the galaxy, and beyond, in pursuit of his greatest foes. The also believe the Khagan is still alive somewhere within the Webway and will one day return to the Chapter and its Successors in a time of great need.
ca. 109.M31 Rise of the Raven Guard Raven Guard N/A For the first time since the disaster of the Drop Site Massacre on Istvaan V, the Raven Guard Chapter finally reaches a significant combat strength not seen in over a standard century.
ca. 121.M31 Battle of Thessala Ultramarines vs. Emperor's Children Traitor Victory Roboute Guilliman continued to serve with the Ultramarines Chapter after the Heresy, leading them for another century after the Second Founding. It is Guilliman's actions subsequent to the Horus Heresy that made him the figure of adoration that he would become. With the Traitors scattered and the Emperor to all intents and purposes lost to Humanity, the Imperium stood at the precipice. It was the genius and leadership of Roboute Guilliman that saw the Imperium through its first full standard century following the Heresy after he took up the position of Lord Commander of the Imperium, keeping new invaders at bay and saving the scattered worlds from collapsing into anarchy. While fighting on the world of Thessala, Roboute Guilliman fell at the hands of his erstwhile brother, the Daemon Primarch Fulgrim of the Emperor's Children Traitor Legion. Poisoned unto death by the stroke of his brother's Chaos-tainted blade upon his neck, Guilliman's barely-living body was placed in a stasis field, and later enthroned in the Ultramarine's fortress-monastery on Macragge in the Temple of Correction. There he remained until 999.M41 during the Ultramar Campaign, when by the grace of the Emperor, the technological genius of Belisarius Cawl and the power of the Eldar god of the dead Ynnead, he was resurrected to once more defend the empire he had worked so hard to build.
211.M31 Disappearance of the Wolf King Space Wolves contingent N/A On the eve of the holiday known as the "Feast of the Emperor's Ascension", which commemorates the day the Emperor defeated Horus and "ascended" back into the Immaterium after being entombed upon the Golden Throne, Leman Russ and his gathered Wolf Lords were gathered for a feast to celebrate. On this occasion, Leman Russ quieted the great hall of his warriors to speak, but then froze in place as his eyes glazed over as if seeing a vision. The assembled Space Wolves looked on in horror as their Primarch fell to his knees and called for his Wolf Guard and closest retainers to attend him, all save the youngest, Bjorn the Fell-Handed. Giving his closest companions his instructions, Russ turned and left the Great Hall with his bodyguard in tow, leaving only Bjorn behind. The tale of his disappearance is retold every thousand standard years by the Dreadnought Bjorn the Fell-Handed, the oldest Astartes Dreadnought still in service in the entirety of the Imperium. After seven standard years of waiting, the Space Wolves elected Bjorn the Fell-Handed as their first Great Wolf, the de facto Chapter Master of the Space Wolves, to rule in Russ' stead until the day of his return. For 10,000 years they have waited, and still the Wolf King has not returned.
ca. 781.M31 The 1st Black Crusade Imperial Fists vs. Forces of Chaos Pyrrhic Loyalist Victory Abaddon the Despoiler, the new Warmaster of Chaos following Horus death, made his first attempt to launch a new offensive against the Imperium of Man following the Horus Heresy when he unleashed the 1st Black Crusade and the First Battle of Cadia. This attempt eventually failed and the Forces of Chaos proved unable to penetrate the Cadian Gate that would allow them to take control of the only truly navigable pathway out of the Eye of Terror and into Imperial space. For the next 10,000 standard years, Abaddon will bend all of his efforts to finding a way to complete what Horus began and launch a Chaotic war that will conquer Terra and eliminate the "Corpse-Emperor." These massive assaults become known as "Black Crusades" to the people of the Imperium. During this first of those epic conflicts, the Imperial Fists Primarch Rogal Dorn supposedly "died" fighting aboard a Chaos Space Marine vessel after leading an assault on a large Chaos warfleet that emerged from the Eye of Terror and vastly outnumbered the Imperial defenders. Seeing the importance of attacking the enemy fleet whilst they were still preparing to invade Imperial space, Dorn relied on hit-and-run attacks until his reinforcements could arrive. Dorn "died" aboard the Chaos Despoiler-class Battleship known as the Sword of Sacrilege after leading a desperate attack on its bridge. When Dorn and his elite Honour Guard stormed the bridge, they were cut down to a man. Later, the Imperial Fists would pick up an escape pod from one of their own starships present at the battle, which contained the weapons and Power Armour of their beloved Primarch. The only sign of Dorn himself was a single skeletal fist that the Imperial Fists believed had belonged to their Primarch. What fate ultimately befell the Primarch of the Imperial Fists, and whether he truly died or not, has yet to be determined with absolute certainty.
ca. 900.M31 Establishment of the Temple of the Saviour Emperor "Fatidicus," the Prophet N/A A highly decorated Imperial Army officer takes the name "Fatidicus," meaning "prophet," and secretly establishes the Temple of the Saviour Emperor on Terra in violation of the atheistic doctrines of the Imperial Truth. His teachings will eventually spread across the entire newborn Imperium of Man, via the Imperialis Auxilia and Armada Imperialis, leading to the foundation of the Adeptus Ministorum as the eventual state church of the Imperium in the middle of the 32nd Millennium. The Imperial Truth becomes a forgotten relic of the past, as dead as the dream of a benevolent Imperium. The High Lords of Terra accept the growth of faith in the Emperor as the God of Mankind across the galaxy, seeing in the new religion a powerful potential tool for morale-building and political control.

See Also

Battles of the Horus Heresy
004-006.M31 Battle of ProsperoIstvaan III AtrocityWar Within the WebwayBattle of the Somnus CitadelUnrest on CalibanSignus CampaignSchism of MarsBattle of DiamatDrop Site MassacreFirst Battle of ParamarBattle of the Coronid Deeps
007-008.M31 Battle of PhallBattle of RavendelveBattle of the Alaxxes NebulaSiege of the Perfect FortressChondax CampaignSecond Battle of ProsperoFirst Siege of Hydra CordatusBattle of the Furious AbyssBattle of CalthBattle of ArmaturaShadow CrusadePercepton CampaignBattle of IydrisThramas CrusadeFall of Baztel IIIBattle of VannaheimSecond Battle of ParamarBattle of Constanix IISiege of Epsilon-Stranivar IXTreachery at Port MawManachean WarMezoan CampaignBattle of BodtBattle of DwellBattle of Molech
009-010.M31 Xana IncursionCarnage of MoroxSangraal CampaignLiberation of NuminalBattle of ArissakBattle of PerditusBattle of SothaScouring of Gilden's StarBattle of NyrconBattle of TallarnBattle of NocturneBattle of Pluto
011-014.M31 Malagant ConflictBattle of the Kalium GateBattle of CatallusBattle of TralsakTarren SuppressionBalthor Sigma InterventionScouring of the Ollanz ClusterBattle of ZepathBattle of AnuariBattle of PyrrhanSecond Battle of DavinBattle of TrisolianBattle of YarantBattle of KradeBattle of DelugeBattle of Heta-GladiusBattle of the Aragna ChainBattle of KallethBattle of the Diavanos SystemBattle of DesperationBattle of Beta-GarmonDefence of RyzaBattle of ThagriaSolar WarRaid on LunaSiege of TerraGreat Scouring


  • Codex: Chaos Space Marines (6th Edition), pp. 6, 8-12, 14, 20, 23, 40, 48, 57, 62, 69
  • Codex: Chaos Space Marines (4th Edition), pp. 12-15, 22, 46
  • Codex: Chaos Space Marines (3rd Edition, 1st Revision), pp. 4-5, 44
  • Codex: Chaos Space Marines (3rd Edition), pg. 22
  • Codex: Chaos (2nd Edition), pp. 8-11, 17-18, 98-99
  • Codex: Grey Knights (5th Edition), pg. 6
  • Codex Imperialis (2nd Edition), pp. 10, 16, 20
  • Dark Heresy: Blood of Martyrs (RPG), pg. 7-9, 27, 104-105
  • Dark Heresy: Daemon Hunter (RPG), pg. 7
  • Dark Heresy: The Radical's Handbook (RPG), pp. 78, 80, 93, 120
  • Deathwatch: Core Rulebook (RPG), pp. 12-13, 39, 41, 43-45, 48-49, 53, 79, 164, 182, 322-323, 361
  • Deathwatch: First Founding (RPG), pp. 4, 7, 14, 16, 21, 27-28, 41, 47, 54, 67, 76-94, 116, 127
  • Deathwatch: Honour the Chapter (RPG), pp. 5, 9, 13, 60, 66, 74, 82, 89, 104, 139,
  • Index Astartes I, "The Unforgiven - The Dark Angels Space Marine Chapter," "Children of the Emperor - The Emperor's Children Space Marine Legion," "Bitter and Twisted - The Iron Warriors Space Marine Legion," "Lightning Attack - The White Scars Space Marine Chapter," "Blood Frenzy - The Flesh Tearers Space Marine Chapter," "Warriors of Old - Space Marine Dreadnoughts," "Psykana Librarius - Space Marine Librarians"
  • Index Astartes II, "Wolves of Fenris - The Space Wolves Space Marine Chapter," "Emperor's Fist - The Imperial Fists Space Marine Chapter," "Bringers of Darkness - The Night Lords Space Marine Legion," "Angels of Death - The Blood Angels Space Marine Chapter," "Righteous Zeal - The Black Templars Space Marine Chapter," "For the Emperor - Space Marine Chaplains"
  • Index Astartes III, "Hand of Justice - The Iron Hands Space Marine Chapter," "Chosen of Khorne - The World Eaters Space Marine Legion," "Warriors of Ultramar - The Ultramarines Space Marine Chapter," "The Lost and the Damned - The Death Guard Space Marine Legion," "Masters of Forbidden Knowledge - The Thousand Sons Space Marine Legion"
  • Index Astartes IV, "Sons of Horus - The Black Legion Space Marine Legion," "Dark Apostles - The Word Bearers Space Marine Legion," "Promethean Warriors - The Salamanders Space Marine Chapter," "Claws of the Raven - The Raven Guard Space Marine Chapter," "The Enemy Within - The Alpha Legion Space Marine Legion," "Bloodied Fist - The Crimson Fists Space Marine Chapter," "Deep Strike - Tactical Dreadnought Armour"
  • Realm of Chaos: The Lost and the Damned (2nd Edition), pp. 9, 164, 177-184
  • Realm of Chaos: Slaves to Darkness (2nd Edition), pp. 240-241, 243-244, 268
  • The Horus Heresy - Book One: Betrayal (Forge World Series) by Alan Bligh
  • The Horus Heresy - Book Two: Massacre (Forge World Series) by Alan Bligh
  • The Horus Heresy - Book Three: Extermination (Forge World Series) by Alan Bligh
  • The Horus Heresy - Book Four: Conquest (Forge World Series) by Alan Bligh
  • The Horus Heresy - Book Five: Tempest (Forge World Series) by Alan Bligh
  • The Horus Heresy - Book Six: Retribution (Forge World Series) by Alan Bligh
  • The Horus Heresy - Book Seven: Inferno (Forge World Series) by Alan Bligh, pp. 22-32, 38, 65
  • The Horus Heresy - Book Eight: Malevolence (Forge World Series) by Neil Wylie and Anuj Malhotra, pp. 12-13
  • The Horus Heresy: Collected Visions (Background Book)
  • Visions of Heresy (Artbook) by Alan Merrett
  • Warhammer 40,000 Rulebook (6th Edition), pp. 137, 158, 160-161, 168, 183, 186, 225, 228, 380, 403
  • White Dwarf 332 (US), "Chaos Space Marines", pg. 16
  • White Dwarf 274 (US), "Chapter Approved: Chaos Space Marine Legions"
  • White Dwarf 268 (US), "Assault on Holy Terra", "Abaddon the Despoiler" & "Index Astartes First Founding: Sons of Horus, The Black Legion Space Marine Chapter"
  • White Dwarf 265 (AUS), "Index Astartes - The Death Guard"
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  • Promethean Sun (Novella) by Nick Kyme
  • Feat of Iron (Novella) by Nick Kyme
  • False Gods (Novel) by Graham McNeill
  • Galaxy In Flames (Novel) by Ben Counter
  • Flight of the Eisenstein (Novel) by James Swallow
  • Fulgrim (Novel) by Graham McNeill
  • The Reflection Crack'd (Novella) by Graham McNeill
  • Descent of Angels (Novel) by Mitchel Scanlon
  • Legion (Novel) by Dan Abnett
  • Battle For the Abyss (Novel) by Ben Counter
  • Mechanicum (Novel) by Graham McNeill
  • Tales of Heresy (Anthology) edited by Nick Kyme & Lindsey Priestly
  • Fallen Angels (Novel) by Mike Lee
  • A Thousand Sons (Novel) by Graham McNeill
  • Nemesis (Novel) by James Swallow
  • The First Heretic (Novel) by Aaron Dembski-Bowden
  • Prospero Burns (Novel) by Dan Abnett
  • Age of Darkness (Anthology) edited by Christian Dunn
  • The Iron Within (Novella) by Rob Sanders
  • The Last Remembrancer (Novella) by John French
  • The Face of Treachery (Novella) by Gav Thorpe
  • Liar's Due (Novella) by James Swallow
  • Little Horus (Novella) by Dan Abnett
  • Rebirth (Novella) by Chris Wraight
  • Savage Weapons (Novella) by Aaron Dembski-Bowden
  • Rules of Engagement (Novella) by Graham McNeill
  • Forgotten Sons (Novella) by Nick Kyme
  • The Outcast Dead (Novel) by Graham McNeill
  • Deliverance Lost (Novel) by Gav Thorpe
  • Corax: Soulforge (Novella) by Gav Thorpe
  • Know No Fear (Novel) by Dan Abnett
  • The Primarchs (Anthology) edited by Christian Dunn
  • The Serpent Beneath (Novella) by Rob Sanders
  • Brotherhood of the Storm (Novel) by Chris Wraight
  • Know No Fear (Novel) by Dan Abnett
  • Honour to the Dead (Novella) by Gav Thorpe
  • Fear To Tread (Novel) by James Swallow
  • Shadows of Treachery (Anthology) edited by Christian Dunn
  • Aurelian (Novella) by Aaron Dembski-Bowden
  • Army of One (Short Story) by Rob Sanders
  • Angel Exterminatus (Novel) by Graham McNeill
  • Tallarn: Executioner (Novel) by John French
  • Betrayer (Novel) by Aaron Dembski-Bowden
  • The Purge (Novel) by Anthony Reynolds
  • Mark of Calth (Anthology) Edited by Laurie Goulding
  • Dark Heart (Ebook) by Anthony Reynolds
  • The Scripts: Volume 1 (Anthology) Edited by Christian Dunn
  • The Weakness of Others (Short Story) by Laurie Goulding
  • The Crimson Fist (Novella) by John French
  • Prince of Crows (Novella) by Aaron Dembski-Bowden
  • The Lion (Novella) by Gav Thorpe
  • Kryptos (Ebook) by Graham McNeill
  • The Gates of Terra (Ebook) by Nick Kyme
  • Vulkan Lives (Novel) by Nick Kyme
  • Scorched Earth (Novella) by Nick Kyme
  • The Unremembered Empire (Novel) by Dan Abnett
  • Censure (Novel) by Nick Kyme
  • Scars (Novel) by Chris Wraight
  • Ravenlord (Novel) by Gav Thorpe
  • The Devine Adoratrice (Novella) by Graham McNeill
  • Vengeful Spirit (Novel) by Graham McNeill
  • The Damnation of Pythos (Novel) by David Annandale
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  • Strike and Fade (Audio Drama) by Guy Haley
  • Raven's Flight (Audio Drama) by Gav Thorpe
  • Warmaster (Audio Drama) by John French
  • Butcher's Nails (Audio Drama) by Aaron Dembski-Bowden
  • Garro: Oath of Moment (Audio Drama) by James Swallow
  • Garro: Legion of One (Audio Drama) by James Swallow
  • Garro: Sword of Truth (Audio Drama) by James Swallow
  • Garro: Burden of Duty (Audio Drama) by James Swallow
  • Garro: Grey Angel (Audio Drama) by John French
  • Veritas Ferrum (Audio Drama) by David Annandale
  • Wolf Hunt (Audio Drama) by Graham McNeill
  • The Sigillite (Audio Drama) by Chris Wraight
  • Hunter's Moon (Audio Drama) by Guy Haley
  • Templar (Audio Drama) by John French
  • Kharn: The Eightfold Path (Audio Drama) by Anthony Reynolds
  • Cypher: Guardian of the Order (Audio Drama) by Gav Thorpe
  • Lucius: The Eternal Blade (Audio Drama) by Graham McNeill
  • Echoes of Ruin (Audio Drama)
  • Wolf's Claw (Audio Drama) by Chris Wraight
  • Thief of Revelations (Audio Drama) by Graham McNeill
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