Caliban was an Imperial Death World located in the Segmentum Obscurus to the galactic north of the Eye of Terror that was once the homeworld of the Dark Angels Legion of Space Marines. Caliban was destroyed during the conflict between Luther, his Chaos-corrupted Fallen Angels and their Primarch Lion El'Jonson and his Loyalist Dark Angels in a great conflagration immediately following the end of the Horus Heresy.

What little remained of the planet was the territory surrounding Aldurakh, the fortress-monastery of the Dark Angels, which was transformed into a mobile Star Fortress that serves as the primary fortress-monastery and base of operations of the Chapter at present and is known informally as The Rock.


The world of Caliban possessed as cruel and harsh an environment as any in the galaxy. Classified as a Death World by the Imperial astrocartographers, the dark, twisted forests that covered the surface of this lush, green planet were as beautiful as they were deadly. These dangerous woods were infested with creatures known as the Great Beasts who had been warped and mutated into fanatical predators by the unnatural forces of Chaos. Imperial scholars believe this was due to the Caliban System's close proximity to the Eye of Terror. Day-to-day survival was a ceaseless struggle due to the ferociousness of the ravening Great Beasts that infested the Calibanite forests. To tread the forest paths was to invite certain death. The human inhabitants of Caliban were forced to live in huge fortresses and castles located in clearings hacked from the forests of the planet. Cut off from Terra and the rest of Mankind's interstellar community by the Warp Storms that savaged the galaxy during the Age of Strife, human civilisation on Caliban devolved into a semi-feudal state, with most of the population ruled over by a small warrior elite who were very similar in function and form to the medieval European knights of Old Earth's ancient past.

Map Caliban2

Imperial Departmento Cartographicae map detailing the former location of Caliban in the Segmentum Obscurus

The nobility of Caliban were a brusque and pugnacious class. Raised from childhood to live and die by the sword, they were great warriors known for their courage in facing the Great Beasts and other dangers of the Calibanite forests. They fought in a primitive form of Power Armour much like that used by the first Space Marines, and like the Astartes their main weapons were the Chainsword and Bolt Pistol, all weapons derived from humanity's common technological legacy. However, most other forms of advanced technology had been lost to the Calibanite civilisation, and the warrior nobility therefore rode into battle on powerful warhorses known as destriers.

The Calibanite nobility's life was one of constant struggle as they fought against the multitude of Great Beasts that threatened to overrun their small settlements. Sometimes a particularly fearsome creature would stay in one area and terrorise it, in which case the ruler of the community would declare a quest against the monster, and knights from all around the world would come to attempt to kill the beast. Slaying a quest-creature could bring honour and fortune for the knight lucky enough to kill it -- yet more often than not it brought only a bloody and horrific death in the teeth and talons of a hell-spawned abomination.

The Order


A knight of The Order confronts one of the Great Beasts of Caliban.

The brave warrior knights who discovered the young Primarch Lion El'Jonson after his arrival on Caliban through the Warp from Terra belonged to a monastic group known simply as The Order. The Order had a reputation across all of Caliban for the honesty, nobility and fearless skill of its brother-knights in battle. Uniquely amongst the many knightly orders of Caliban, the members, or brothers, of The Order were selected by merit rather than hereditary inheritance. Any Calibanite could join The Order, no matter how low-born they might be. Contingents of brother-knights from the Order travelled across the planet, giving their aid wherever it was needed.

It was while on one of their great expeditions that a band from The Order came upon the wild man who lived in the forests. Thinking him a monster, the knights were ready to kill the Primarch when one of their number, sensing that there was something more to the creature than was apparent, halted his fellows. This young knight, Luther, and his fellow warriors then returned to Aldurukh, their fortress-monastery, taking with them the man born of the forest. Because of his appearance and the place of his discovery, The Order gave the wild man the name of Lion El'Jonson, which meant "The Lion, the Son of the Forest" in the Calibanite dialect of Low Gothic. Jonson easily adapted to the ways of humans, and learned to speak and reason remarkably quickly under the knights' tutelage.

But of his time growing up alone in the forest and what had transpired during that time of his life the Lion never spoke. Within Aldurukh El'Jonson was assimilated into the human society of Caliban. There he and Luther formed a close friendship as Luther became a mentor and foster father for the foundling. The two men forged a tight and affectionate bond based on their complementary personalities. Where Jonson was temperamental and taciturn, Luther was charming and charismatic. Where Luther was rash and emotional, Jonson was a brilliant strategist and implacable once decided upon a course of action. In time, the pair's talents combined to make them an incomparable team. Over the following years Jonson and Luther quickly rose through the ranks of The Order. Their exploits became the stuff of legend on Caliban, and the reputation of The Order rose accordingly.

The number of young warriors wishing to join The Order grew and grew, so that in time many new fortress-monasteries had to be built to contain all of The Order's growing complement of knights and Initiates. As the Order grew in size Jonson and Luther argued for a crusade against the Great Beasts that infested the forests, to cleanse the planet once and for all of their foul presence so that humanity might have a chance to prosper on Caliban as never before. The oratory of Luther convinced the Grand Masters of all the different knightly orders and most of the nobles of the planet to join in the crusade, but it was Jonson's unrivalled talent for planning and organisation which ensured that within the course of a single decade the entire planet of Caliban was cleared of the terrible Chaotic monsters that had once inhabited it. A new golden age dawned for the inhabitants of the once troubled planet.

In recognition of his triumph against the Great Beasts, Lion El'Jonson was proclaimed the new Supreme Grand Master of The Order and Caliban as a whole. Although Luther did not openly begrudge Jonson the great honour he had won, he did feel the pangs of jealousy at what honours might have been his had the Lion never come to Caliban to outshine him. Thus was lit the first small spark of grievance that would lead to the schism that would tear the Dark Angels Legion apart. But all this was in the future -- for all too short a time the people of Caliban enjoyed a season of peace and plenty.

The Emperor and The Lion

Meanwhile, unbeknownst to Jonson and the people of Caliban, the Emperor of Mankind was waging his Great Crusade across the galaxy, reuniting humanity and purging entire star systems of their alien oppressors. As the Imperium's wave of conquest advanced across the galaxy, Imperial Explorators rediscovered the isolated world of Caliban.

Forward reconnaissance elements from the I Legion of Space Marines arrived at Caliban and identified the Lion as one of the Emperor's genetically-engineered missing sons, the Primarchs. Jonson was immediately given command of the I Legion when the Emperor realised he had not only found one of his lost sons, but the genetic father of the very Astartes who had landed on Caliban. Luther and the other members of The Order who passed the Legiones Astartes' trials were transformed into I Legion warriors, either as fully-fledged Astartes if they were young enough to undergo the implantation of the gene-seed organs, or like Luther, through genetic manipulation to increase their size and physical abilities if they were too old for the process. After the new Astartes were ready, Jonson publicly re-named the I Legion the Dark Angels after an old Calibanite myth of shadow-clad angels who came from the sky to aid the people of Caliban in their time of need. Luther, too old to become a true Astartes, was the first member of The Order to be genetically modified and became Jonson's second-in-command, as he had been during the Calibanite crusade against the Great Beasts.

Jonson then left with the Emperor and the newly re-named Dark Angels to take command of his portion of the Great Crusade even as the Imperium began to work extraordinary changes in the culture, technology and lifestyle of the people of Caliban in order to make the world a useful contributor to the needs of the Emperor. Tens of thousands of Calibanites were recruited into newly raised regiments of the Imperial Army, whilst the remainder of the population began work clearing the forests and constructing the great cities needed to house the millions of labourers who would man the manufactorums that would produce materiel for the Great Crusade's forces night and day. Some Calibanites, particularly amongst the nobility, objected to the loss of their old way of life, but such dissent was viewed as treason against the Emperor and was dealt with harshly by the Imperial forces that were now stationed on the former Death World.

The Great Schism

Luther - Great Betrayer

Luther, Arch-Betrayer and leader of the Fallen Angels

The Lion was granted command of the 4th Expeditionary Fleet of the Great Crusade in orbit of the planet Sarosh. The Saroshi - ruled by a bureaucracy - had recently expressed their interest in becoming part of the Imperium, and the Imperials were eager to allow them in, believing that these people seemed to express the same secular beliefs as they did in the Imperial Truth. But the Saroshi (without mentioning it to the Imperial expedition) secretly worshipped Chaotic entities in the Warp they called the Melachim, and saw the anti-religious stance of the Pre-Heresy Imperium's Imperial Truth as unsuppressed evil. The Lord High Exacter, the leader of the Saroshi bureaucracy, denounced Jonson and the Emperor to the Primarch's face aboard the Dark Angels' flagship Invincible Reason, and Lion El’Jonson responded by ramming his Power Sword through the fanatical Saroshi leader's body. Unknown to the Dark Angels, the Saroshi had secreted a nuclear device aboard their shuttle, intending to assassinate the fleet's entire command structure, including Jonson; however, Luther and a junior Librarian named Zahariel managed to eject the shuttle into space, causing only minor damage to the flagship though Zahariel suffered serious burns from the shuttle's engines. After this incident, Luther, Zahariel and 500 other Dark Angels were sent back to Caliban in disgrace for allowing an enemy to get a nuclear device aboard the Primarch's flagship and officially to oversee the recruitment of new Space Marines into the I Legion from the Calibanite population. In truth, the Lion also had his suspicions about Luther, who he believed, rightly, had at first thought to allow the Saroshi device to succeed in killing the Primarch so that he might at last have the position of true leadership that he had lost ever since discovering the Lion in the forests of Caliban.

Decades passed and Luther remained in charge of the Dark Angels' garrison force on Caliban. he and the Astartes under his command were never recalled by his Primarch to combat duty in the Great Crusade. As Jonson's fame spread throughout the galaxy and reports of his great deeds and prowess in battle reached the I Legion's homeworld, Luther felt robbed of his share of the glory. He wanted the fame and recognition that he felt he deserved as Jonson's equal and mentor. His role as the Planetary Governor of what had become a half-forgotten backwater world seemed more and more to him like an insult. The seed of jealousy and dissension that had been planted within Luther when Jonson was made the Supreme Grand Master of The Order now began to grow and rankle within his heart as the Primarch became more and more celebrated across the Imperium.

The Destruction of Caliban

Destruction of Caliban

The Dark Angels homeworld coming apart during the final confrontation between Primarch Lion El'Jonson and the Arch-Betrayer Luther

After the end of the Horus Heresy during the Battle of Terra, Lion El'Jonson and the Dark Angels fleet finally returned to Caliban, but once the I Legion's vessels made orbit they were immediately fired upon by Caliban's orbital defence system. Puzzled, El'Jonson withdrew his vessels into the outer reaches of the Caliban System. When he learned that Luther had ordered Caliban's defences to fire upon the returning Dark Angels fleet, El'Jonson fell into a terrible rage, believing that Luther and the Dark Angels garrison left on Caliban had fallen to the temptations of Chaos just like the Astartes of the Traitor Legions. The Lion ordered his fleet to launch an orbital bombardment of the planet and destroy the weapons of the orbital defence systems. The Legion's fleet bombarded the planet mercilessly, causing the tectonic plates of the planet to crack and shift. El'Jonson then personally led an Astartes strike force into the Tower of Angels, the I Legion's primary fortress-monastery on Caliban and duelled his former friend and mentor to the death. They were equally matched, but finally, Luther keeled over in exhaustion, leaving him open to a deathblow. Yet for all his wrath, El'Jonson could not bring himself to slay his foster father and so, in that moment, Luther lashed out with a psychic attack using the sorcerous powers that had been granted to him by his willing acceptance of servitude to the Ruinous Powers. Yet as Luther saw his oldest friend dying, his mind finally cleared of its jealousy and hate, as if a veil had been lifted, and he fell to his knees in anguish, sending out a cry for help into the Warp. The Ruinous Powers, angered that they had lost such a valuable pawn in their plans to weaken the Imperium, sent a massive Warp Storm to wrack the surface of the planet.

The world of Caliban then broke apart under the strain produced by the Warp Storm and the prior geological stresses unleashed by the Dark Angels' orbital bombardment. The entire world imploded into a field of orbital debris, with the exception of the oldest and mightiest fortress-monastery of The Order, which had been protected by potent defensive gravitic forcefields.

Destruction of Caliban2

Caliban explodes

Officially called the "Tower of Angels," but better known as The Rock, the Calibanite bedrock upon which the fortress sat was later hollowed out by the Dark Angels, fortified with advanced Imperial weaponry and fitted with a Warp-Drive to transform it into a mobile Star Fortress which would serve as the Dark Angels primary fortress-monastery.

Immediately following the destruction of Caliban, when the Dark Angels searched the ruins of the Tower of Angels, they found the Arch-Traitor Luther, babbling incoherently that Lion El'Jonson had been taken by the Watchers in the Dark (supposedly to heal from his psychic attack), but I Legion's Primarch was nowhere to be seen, nor could any trace of his body be found where he had duelled Luther. The rest of the Dark Angels Astartes who had been converted by Luther to the worship of Chaos were sucked into the Immaterium by the will of the Chaos Gods and were scattered across time and space. From that time forward they were forever after referred to as the Fallen Angels or simply the Fallen, and are hunted ruthlessly by the Dark Angels and their Successor Chapters, who call themselves the Unforgiven. All bear the haunted legacy of lost Caliban and all have pledged that they shall never rest until every one of the Fallen has repented his sins against the Emperor.


Caliban is the name of a character in the Shakespearean play "The Tempest." Caliban is forced into servitude on an island ruled by Prospero the magician. Growing up alone on the deserted island, he is often depicted as a wild man, or a deformed man -- the only human inhabitant of the island that is otherwise "not honour'd with a human shape" (Prospero, I.2.283). Caliban is the son of a luciferous woman (witch) resulting in his feral nature. Upon the magician's arrival to the island, Caliban teaches Prospero how to survive, while he is eventually civilised by the magician and Prospero's daughter Miranda who teach him religion and how to speak. Following Caliban's attempted rape of Miranda, he was compelled by Prospero to serve as the magician's slave. In slavery, Caliban came to view Prospero as an usurper and grew to resent him and his daughter. He sought to rebel against them under a new master, but in the end he remained a faithful servant to his first master, Prospero. This character arc has notable similarities to those of the Dark Angels' Primarch Lion El'Jonson and Luther.

Caliban might also be an anagram for "Canibal" or derived from the word Kaliban/Calibaun, the Romany (gypsy) word for the colour "black." Coincidentally, the original colour of the Power Armour and panoply of the Dark Angels Legion during the Great Crusade and the Horus Heresy was black. Caliban is also the name of the second largest of the retrograde irregular moons of Uranus, the seventh planet of the Solar System.


  • Codex: Dark Angels (6th Edition), pp. 6-12, 18-19, 26, 47
  • Codex: Dark Angels (4th Edition)
  • Codex: Dark Angels (3rd Edition)
  • Codex: Angels of Death (2nd Edition)
  • Codex: Eye of Terror, pp. 12, 16
  • Index Astartes I - "The Unforgiven," pp. 4, 13, 18-23
  • Angels of Darkness (Novel) by Gavin Thorpe
  • Descent of Angels (Novel) by Mitchel Scanlon
  • Fallen Angels (Novel) by Mike Lee
  • The Thirteenth Black Crusade (Background Book), pp. 20, 30, 48, 74, 79, 84
  • Warhammer 40,000 Rulebook (5th Edition), p. 129
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