|Sons of Guilliman|
Unknown (sometime in the 33rd Millennium)
Blue and White
- The Siege of Lakadamon (953.M33) - The Sons of Guilliman, alongside several Tekarn armoured regiments are besieged in the defence of the Hive World of Lakadamon by the hordes of the Ork Warboss Vorhgad Bloodfang. Despite vastly overwhelming odds, the Chapter successfully holds the planet's defence for three years until the siege is broken by the combined forces of the Night Reapers and War Bearers Chapters, fighting alongside a major taskforce from Battlefleet Tempestus to break the orbital blockade that encircles the beleaguered world.
- Cleansing of Salinas (Unknown Date.M41) - At an uncertain time in Imperial history, the Sons of Guilliman battled the Forces of Chaos on the world of Salinas. The exact nature of the Chaos forces is uncertain, but the Salinas records make mention of armoured warriors who could bend reality, and red-fleshed beasts that could swallow a man whole (these seem to bear a striking resemblance to the Unfleshed who later assaulted the capital city of Salinas). The records tell of a great battle near the city of Khaturian, where the Sons of Guilliman's force was completely wiped out. Later, a force of other Astartes described as, "giants in silver armour who smote the vile foe with lightning and faith," (presumably Grey Knights) came to the world and, after cleansing it, took the remains of the lost Sons of Guilliman back to their Chapter. However, 19 fallen warriors, along with their Power Armour, were buried under a collapsed building, and their bodies were only uncovered decades later. It should be noted that one such suit was worn briefly by Uriel Ventris of the Ultramarines. After restoring one of the Mk VI suits to full functionality, Captain Ventris wore this suit to combat the Unfleshed. All of the suits were eventually returned to the Sons of Guilliman, with Ventris' suit declared a Chapter relic.
- Judgement of Hellenus (801.M41) - Inquisitor Hector Rex assumes direct control over the entire 279th Assault Armada of the Imperial Navy and orders the mutant population of Hellenus purged for crimes against genetic purity. At the height of this purge, a combined strike force consisting of Space Marines form the Sons of Guilliman, the Iron Lords and the Skull Bearers Chapters is gathered together to confront the mutant abominations holding the enemy capital. During this confrontation, the Iron Lords contingent becomes tainted by the mutants' hideous gene-taint, forcing their fellow Space Marines to purge them as well.
- Third War for Armageddon (999.M41) - The Sons of Guilliman participated in the Third War for Armageddon, committing 6 companies to the conflict against the massive Ork WAAAGH! of Ghazghkull Thraka.
Chapter Combat Doctrine
The Chapter's order of battle is organised around the tenets of the Codex Astartes.
Notable Sons of Guilliman
- Adharon (Excommunicate Traitoris) - A former Space Marine Captain of the Sons of Guilliman Chapter, Adharon was corrupted by Chaos and gathered a warband of like-minded corrupted Astartes around himself from his former company, known as Adharon's Reavers, to raid and pillage the commerce of the Imperium of Man in the name of the Dark Gods. The Siege of Vraks represented the first time that Adharon's Reavers had operated in concert with other Chaos Space Marine forces.
- Constantinius the Liberator (Excommunicate Traitoris) - Constantinius the Liberator is a former squad Sergeant of the Sons of Guilliman who turned to Chaos. He led the planet of Nova Terra in a rebellion against the Imperium of Man.
The Sons of Guilliman wear quartered, alternating blue and white Power Armour. The Chapter has been shown with both red and yellow Aquilas. The Insignium Astartes states that the Chapter denotes its companies by the colour of the left knee plate and the shoulder plate trim. The right shoulder is blank and is used to display collected company awards, purity seals and the like.
The Chapter badge is an inverted Greek letter Omega, imposed over a pair of wings.
- Codex: Armageddon (3rd Edition), pg. 30
- Codex: Chaos Space Marines (4th Edition), pp. 18-19
- Imperial Armour Volume Two, Second Edition - War Machines of the Adeptus Astartes, pp. 17, 21
- Imperial Armour Volume Seven - The Siege of Vraks - Part Three, pp. 140, 172
- Insignium Astartes, pg. 63
- The Killing Ground (Novel) by Graham McNeill