Barbarus was the poison-choked homeworld of the Death Guard and the planet where Mortarion grew up. It’s a key piece of Horus Heresy lore because it shaped the XIV Legion’s identity and was later destroyed by the Dark Angels.
What was Barbarus like?
Barbarus was a feral death world orbiting a dim yellow sun. Its atmosphere was thick with virulent gases and constant fog, making it dark and dismal with only short, shadowy days. Humans could only survive in the valleys and low plains below the fog, where deadly predators roamed at night.
The planet was dominated by the Overlords, a cruel xenos species that could resist the toxic air. They built grey keeps in the mountains and enslaved the human population. Mortarion landed on Barbarus and eventually led a revolt that toppled the Overlords before he joined the Emperor.
Barbarus after the Imperium arrived
Once Barbarus joined the Imperium, the full truth about its conditions and the Overlords was kept hidden. Those who knew what really happened either went silent or disappeared. The Imperial War Council forbade access to the system, leaving it under the XIV Legion’s control.
Mortarion refused to move the people to a cleaner world, declaring that Barbarus belonged to them, paid for by generations of blood and terror. Many of the human Death Guard who’d fought beside him became a new ruling class. Within a few years, the planet became a recruitment factory for the Legion, since the natives were naturally resistant to contagion and toxins. Its forges also made Terminator armour for the Death Guard.
The Siege and destruction of Barbarus
During the Horus Heresy, Barbarus was the centre of Mortarion’s Realm of the Reaper. In 013.M31, the vengeful Dark Angels, led by Lion El’Jonson, invaded the system with allies from the Raven Guard and Space Wolves. They destroyed the Death Guard’s orbital defences and landed on the surface.
The traitors put up stiff resistance, especially the Iron Warriors who’d taken refuge there, but the Loyalists won. Shortly before the Siege of Terra, the Invincible Reason destroyed Barbarus from orbit with Cyclonic Torpedoes. The planet was gone.
Key facts
- Barbarus was the Death Guard’s homeworld and where Mortarion landed.
- It was a toxic death world ruled by xenos Overlords before Mortarion’s revolt.
- The planet became a key recruitment and manufacturing centre for the XIV Legion.
- During the Horus Heresy, it was the centre of Mortarion’s Realm of the Reaper.
- The Dark Angels destroyed Barbarus with Cyclonic Torpedoes in 013.M31.
FAQ
Why was Barbarus destroyed?
The Dark Angels destroyed Barbarus during the Horus Heresy as revenge against the Death Guard. They bombarded it with Cyclonic Torpedoes shortly before the Siege of Terra.
Who led the attack on Barbarus?
Lion El’Jonson commanded the Loyalist forces, with support from Leman Russ and the Space Wolves, plus the Raven Guard.
What was Barbarus’s role in the Death Guard?
It was their homeworld and main recruitment world. Its toxic environment produced resilient recruits who were ideal for Space Marine conversion.