Ullanor Prime was a world in the Ullanor System of the Ullanor Sector of the galaxy that was heavily settled by Orks, becoming the heart of not one, but two massive Ork Empires that faced the military forces of the Imperium of Man in the 30th and 32nd Millennia.
The first of these Greenskin empires based on Ullanor Prime was approximately twelve star systems in size and was ruled by the Overlord Urrlak Urruk at the end of the 30th Millennium. It was defeated by a massive Imperial force led by the Primarch Horus Lupercal and his Luna Wolves Legion in ca. 000.M30 during what was known as the Ullanor Crusade and marked the greatest triumph of the wider Great Crusade. Following it, a great Imperial celebration known as the Triumph of Ullanor was held where the Emperor granted Horus the rank of Warmaster. The Master of Mankind also shocked the assembled Primarchs and their Astartes when He announced His own retirement from the campaigns of the Great Crusade so that He could return to Terra and began a secret project to open up the Webway for the use of humanity. This event marked both the high watermark of the Great Crusade and the beginning of the tensions between the Emperor and the Primarchs that would help to bring on the Horus Heresy.
The second great Ork Empire to arise on Ullanor Prime initiated what was known as the War of the Beast in the 32nd Millennium from 544-546.M32. Under the rule of The Beast, the Orks established the most technologically and culturally sophisticated civilization they had ever created on Ullanor Prime and sought vengeance against the Imperium of Man for their defeat during the Ullanor Crusade. In the course of the conflict, the Greenskin forces threatened Terra itself multiple times until following three separate Imperial invasions the Emperor's servants finally succeeded in cleansing the world of its Ork population for a final time.
In the wake of the War of the Beast, the Adeptus Mechanicus sought to scavenge the remains of the Orks' highly advanced technologies from the battered planet in violation of Imperial restrictions on the use of xenos technology. To do so, they used the Orks' "subspace" teleportation technology to teleport Ullanor Prime to a new star system on the edge of the Segmentum Solar and then reported that the world had actually been destroyed to the Senatorum Imperialis. The Mechanicus proceeded to strip the planet bare and then leave it open for later Imperial colonisation to further hide their subterfuge. Centuries later, Ullanor Prime was unwittingly colonised by humanity and given a new name, a name that would find its own place in history before long -- Armageddon.
A vast Imperial assault was launched against Ullanor Prime, the seat of the Ork Empire of the Overlord Urrlak Urruk, the largest such Greenskin empire ever encountered in Mankind's history to that time. The Crusade included the deployment of 100,000 Astartes from the Luna Wolves, White Scars and Ultramarines Legions, 8,000,000 Imperial Army troops, 100 Titans of the Legio Mortis and 600 starships of the Imperialis Armada and their support personnel. The Ullanor Crusade marked the high point of the Great Crusade's vast effort to reunite the scattered colony worlds of humanity under the rule of the Emperor in the wake of the Age of Strife. Led by the superlative strategic mind of the Luna Wolves Legion's commander, the Primarch Horus Lupercal, the massive Ork Overlord was defeated and the Greenskin forces scattered.
Following this monumental victory, a great Imperial triumph, remembered as the Triumph of Ullanor, was held for the participating forces. It was there that the Emperor of Mankind announced that He would no longer be leading the Great Crusade and intended to return to Terra. In His place to command the vast forces of Mankind he left the Primarch Horus. Horus was granted the new;y-created rank of Imperial Warmaster and assumed command authority over all of his fellow Primarchs and every Expeditionary Fleet of the Great Crusade, sowing the seeds of dissension, pride and wounded feelings that would eventually fester and erupt into all-out civil war during the Horus Heresy.
War of the Beast
Nearly 1,500 standard years later, in 544.M32, a massive Ork WAAAGH! led by a mysterious Warlord known only as The Beast rampaged across the Imperium, growing in size until it became the greatest Greenskin invasion that the galaxy had known to that date, eclipsing even the one defeated by Horus upon Ullanor Prime at the height of the Great Crusade. The Beast centred his empire upon the long-forgotten world of Ullanor Prime, which by that time had become heavily urbanised by the industrious Greenskins, who covered nearly the entire planet in surprisingly well-organised settlements. The seat of The Beast's empire was the Ork capital city of Gorkogrod, built within a massive temple-Gargant on the exact location where the Emperor and the Primarchs had gathered during the Triumph of Ullanor over a millennia earlier. It was The Beast's intent to use Ullanor Prime as the template to perfect the Ork's Attack Moon concept. Converting the entire planet into a mobile battlestation capable of teleporting itself through the multidimensional realm known only as "subspace," The Beast intended to use Ullanor Prime to destroy Terra itself, eliminating the home of the species that had long been the greatest enemy of the Greenskins.
After the world of Ullanor Prime was identified as the original home of The Beast and his massive WAAAGH!, Vulkan, the immortal Perpetual and long-missing Primarch of the Salamanders Legion, led the First Invasion of Ullanor. Together, the Astartes Chapters of Rogal Dorn's lineage who comprised the Terra defence initiative known as the "Last Wall" invaded The Beast's capital world, focusing upon the capital city of Gorkogrod. At the battle's conclusion, Vulkan charged into The Beast's massive temple-Gargant, intent on facing the Ork Warlord alone. During their confrontation, Vulkan destroyed the temple-Gargant in a massive explosion, which seemed to obliterate both Vulkan and The Beast. This shattered the cohesion of The Beast's Greenskins, whose resistance collapsed in the wake of the defeat of their powerful Warlord. However, unknown to the Imperial forces, the Greenskin presence secretly endured on Ullanor Prime.
A Second Invasion of Ullanor was eventually launched by the Imperium which included several battered Adeptus Astartes Chapters, the newly created Deathwatch, several Astra Militarum regiments, Frateris Templar, Skitarii and Legio Cybernetica cohorts, several Imperial Knight Houses, Inquisitorial Storm Troopers, a small cohort of the Sisters of Silence and a Warlord and Warhound Titan. During the second attack on the city of Gorkogrod, an elite assassination force comprised of several Astartes and other supporting Imperial forces discovered that there were in fact six "Beasts" -- each a "Prime-Ork," a Beast in their own right, and a commander of their own Greenskin "Legion," in mockery of the Emperor and His Primarchs and the ancient Space Marine Legions. When Koorland, the Lord Commander of the Imperium and the sole surviving member of the original Imperial Fists Chapter was killed, the Imperial forces were forced to flee with their fallen commander's body and withdraw from Ullanor.
Not long after this defeat, Maximus Thane, the Chapter Master of the Fists Exemplar, led the final desperate Imperial campaign of the War of the Beast during the Third Invasion of Ullanor. The Imperial forces unleashed redirected asteroids as weapons of mass destruction to devastate the Ork-held planet. With the help of the Sisters of Silence and a captured Ork Weirdboy, the null effect of the anti-psyker Silent Sisters joined with the Weirdboy's powers and created a reverse-WAAAGH! effect that utterly devastated the Greenskin hordes of The Beast. During this final confrontation, The Beast was slain.
After the War of the Beast concluded, Maximus Thane assumed command over the Imperial Fists. He was elected the new Lord Commander of the Imperium by the Senatorum Imperialis and ordered the Adeptus Mechanicus to enact an Exterminatus upon Ullanor Prime to erase its memory from history and prevent a new Beast from ever arising. However, the Adeptus Mechanicus was reluctant to carry out the order, as its Tech-priests knew that Ullanor was rich with unclaimed alien technology that had nearly brought the Imperium to its knees.
For the servants of the Machine God, the acquisition of knowledge superseded all other considerations. Coveting Ullanor Prime and its xenos secrets for himself, Fabricator-General Kubik instead acted in direct contravention of the Lord Commander's orders. By reverse-engineering Ork "telyporta" technology that had been used to move the Ork Attack Moons through "subspace" during the recent conflict, the Adeptus Mechanicus was able to secretly teleport the entire world of Ullanor Prime through the Warp to a new location on the edge of the Segmentum Solar. The uninhabited star system where Ullanor was moved had already been marked for colonisation by the Imperium.
The Fabricator-General reported back to the High Lords of Terra that the Ork World had been cast into the heart of the nearest blue supergiant star -- Ullanor was no more. The Fabricator-General then set out to have Ullanor Prime stripped to its core of useful xenos technology. No trace of the Orkish presence upon the world would be left to reveal the truth of the Mechanicus' deception if the planet was later explored or settled by the Imperium.
Within only a few standard centuries, the world once known as Ullanor became a prime location for human settlement due to its virgin status and strategic location in the Segmentum Solar. Once colonised, Ullanor eventually came to be known by a new name, one that would echo down the millennia and become a pivotal point of contention between the Greenskin races and Mankind -- Armageddon.
- Index Astartes IV, "Sons of Horus - The Black Legion Space Marine Legion"
- Horus Rising (Novel) by Dan Abnett
- Fear to Tread (Novel) by James Swallow, Interlude: Ullanor
- I Am Slaughter (Novel) by Dan Abnett, Ch. 30
- The Beast Must Die (Novel) by Gav Thorpe, Chs. 18-22
- The Last Son of Dorn (Novel) by David Guymer, Chs. 17-18
- Shadow of Ullanor (Novel) by Rob Sanders, Chs. 7-11
- The Beheading (Novel) by GuyHaley, Ch. 5