|Map||Basic Data||Planetary Image|
|Class:||Ork World, later heavily modified planetoid battlestation.|
By M31, Ullanor Prime was the center of a vast Ork empire under the Warboss Urlakk Urg. During the famous Ullanor Crusade, Imperial forces under Horus Lupercal broke the Greenskins power and the Primarch earned the title Warmaster. Under the orders of the Emperor himself the planet was heavily modified by the Adeptus Mechanicus and became the site of the most famous Imperial parade in history, the Ullanor Triumph.
Following the Battle of Beta-Garmon Horus instructed a general order for all of his forces to muster at Ullanor in preparation for the drive on Terra. Ultimately, Fulgrim, Perturabo, Angron, Magnus, Alpharius, and Lorgar arrived with their forces as well as well as disparate Night Lords. The traitor's then enacted a darker version of the original Ullanor Triumph, parading themselves before the assembled Primarch's. At the conclusion of the Triumph, each fleet sacrificed 1/10th of their slaves to the Chaos Gods to allow for safe and easy passage through the Warp on their way to Terra.
1,500 years later, a massive Ork Warboss of unparalleled power known simply as The Beast appeared on Ullanor, making it the center of his empire. The world became heavily urbanized by the Orks, covering nearly the entire planet in surprisingly well-organized settlements. The Beast made his home in the capital city of Gorkogrod, building a massive temple-Gargant at the exact spot where the Emperor and Primarchs gathered during the Ullanor Triumph centuries earlier. The Beast used Ullanor as a template to perfect his Attack Moon concept, converting the entire world into a battlestation that would eventually be used to destroy Terra.
Eventually, the Imperium under the returned Vulkan led a second invasion of Ullanor to slay The Beast. This battle was far different than the first Imperial crusade, seeing the Imperials fight bitter urban warfare against an enemy that refused to fight out in the open. Vulkan eventually was able to lead an Astartes strikeforce into Gorkogrod's temple-gargant, where he dueled The Beast directly. After seemingly sacrificing himself to slay The Beast, Ork resistance on Ullanor crumbled.
The Greenskin presence on Ullanor once again endured however, and in the third invasion of Ullanor (though it was the second during the War of the Beast) it was revealed that there were in fact six "Beasts", each a Prime-Ork commanding a "Legion" of Greenskins. Imperial forces were forced to flee the planet after Lord Commander Koorland was killed.
Shortly after the death of Koorland, Maximus Thane led a third and final Imperial invasion of Ullanor. During this attack, the Imperials used redirected asteroids to devastate the planet. Using the Sisters of Silence in conjunction with a captured Ork Psyker, The Beast was slain. After the war Thane, now Lord Commander, ordered that the Adeptus Mechanicus enact Exterminatus on Ullanor to erase it from history and prevent a new Beast from ever arising. However Fabricator-General Kubik coveted the Greenskin artifacts on the world, and instead used his reverse-engineered Ork teleportation technology to teleport Ullanor to a secret location in Segmentum Solar, which later became Armageddon.
- 1: I Am Slaughter (Novel) Chapter 30
- 2: The Beast Must Die (Novel) Chapters 18–22
- 3: Fear to Tread (Novel) — Interlude: Ullanor
- 4: The Last Son of Dorn (Novel) Chapters 17–18
- 5: Shadow of Ullanor (Novel) Chapters 7–11
- 6: The Beheading (Novel) Chapter 5
- 7: Slaves to Darkness (Novel) — Chapter 19