Roboute Guilliman, Primarch of the Ultramarines, built the realm of Ultramar, held the Imperium together after the Horus Heresy, wrote the Codex Astartes and, after ten thousand years in stasis, returned as Lord Commander of the Imperium.
Roboute Guilliman at a glance
| Primarch of | the XIII Legion |
| Legion | XIII: Ultramarines |
| Homeworld | Macragge |
| Wargear | The Emperor's Sword, the Hand of Dominion, the Armour of Fate |
| Allegiance | Loyalist |
| Status | Alive: Lord Commander of the Imperium |
Who is Roboute Guilliman?
Guilliman is the Primarch who builds. Where his brothers were warriors first, he was a general, an administrator and a lawmaker of genius. He is also the only loyal Primarch active in the current 40K setting, which makes him the most important living figure in the Imperium after the Emperor himself.
Macragge and Ultramar
Guilliman's capsule landed on Macragge, where he was found and adopted by the consul Konor. He grew up learning war, politics and law. While he was away fighting, a noble named Gallan seized the capital and Konor was killed; Guilliman crushed the revolt and became consul himself. He rebuilt Macragge, then united the nearby worlds into Ultramar, a realm of around five hundred worlds that ran better than any part of the Imperium.
The Great Crusade
When the Emperor reached Macragge, Guilliman took command of the XIII Legion, the Ultramarines. It grew into the largest Legion of the Great Crusade. Guilliman did not just conquer worlds: he left them with working governments, defences and supply lines, so they kept producing soldiers and ships for the Crusade.
Calth and the Heresy
When Horus rebelled, he sent Guilliman and the Ultramarines to muster at Calth alongside the Word Bearers of Lorgar. It was a trap. The Word Bearers struck without warning, Calth's sun was poisoned and the Ultramarines suffered their worst losses ever. The fight went on underground for years, in what became known as the Underworld War.
Imperium Secundus
Cut off from Terra by warp storms, Guilliman feared the Emperor was dead. He founded Imperium Secundus, a back-up empire based on Macragge, and named his brother Sanguinius its emperor, with Lion El'Jonson as its protector. When the truth came out that Terra still stood, the plan was dropped. The decision still troubles Guilliman, and some see it as proof of how close he came to his own kind of betrayal.
The Codex Astartes
After the Heresy, Guilliman led the purge of the traitors and became the Imperium's chief architect. He wrote the Codex Astartes, the military bible of the Space Marines, and ordered the Second Founding: the Legions were broken into Chapters of about a thousand warriors each, so no single commander could ever again turn such power against the Imperium. The Ultramarines' many successor Chapters still follow his teachings.
Wounded by Fulgrim
Guilliman's traitor brother Fulgrim, now a daemon prince, struck him with a poisoned blade. To save his life, the wound was frozen in a stasis field, and for ten thousand years Guilliman sat motionless in the Temple of Correction on Macragge, watched over by his Chapter.
Return and the Indomitus Crusade
As the galaxy split apart in the Great Rift, Guilliman was revived, with help from the Aeldari of Ynnead and the Archmagos Belisarius Cawl. He went to Terra, saw what the Imperium had become, and was named Lord Commander of the Imperium. He launched the Indomitus Crusade with Cawl's new Primaris Space Marines, then returned to defend Ultramar from Mortarion in the Plague Wars. Today he rules a broken Imperium, trying to save an empire that worships his father as a god he never wanted to be.
Roboute Guilliman FAQ
Is Guilliman alive?
Yes. He is awake and leads the Imperium as Lord Commander.
Who wounded Guilliman?
Fulgrim, Primarch of the Emperor's Children, with a poisoned blade after the Heresy.
What is the Codex Astartes?
Guilliman's rulebook for how Space Marine Chapters are organised and fight. Most Chapters follow it.
Who is Guilliman's most famous successor?
Marneus Calgar, Chapter Master of the Ultramarines.
Books to read
- Know No Fear (Dan Abnett)
- Dark Imperium (Guy Haley)
- Ruinstorm (David Annandale)
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Find them as Black Library paperbacks and audiobooks.
Read more in our Ultramarines lore guide and see all 20 Primarchs.
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