Almost nothing is known in Imperial records about the Celebrants. Their only mention in Imperial history is that they were ordered to withdraw from the world of Phaethon IV and instead to take up garrison duty on the Ecclesiarchy's Cardinal World of Nedicta Secundus to protect the holy relics of the Adeptus Ministorum found there from the ravages of the Tyranid Hive Fleet Kraken.
However, this was all part of a carefully staged ruse by the Alpha Legion Chaos Space Marines, supposedly on the direct orders of their Primarch Alpharius himself (who may actually have been his secret twin brother Omegon), to get two companies of the Crimson Consuls Chapter of Space Marines stationed in place on Phaethon IV so that the Alpha Legion could destroy a portion of that Chapter by unleashing the Ork WAAAGH! Wuzghal upon it.
The plan worked and the Crimson Consuls on Phaethon IV and elsewhere in the galaxy were ultimately wiped from the rolls of the Emperor's Astartes through the machinations of the insidious Alpha Legion.
- False Flags (799.M39) - An Imperial Navy deep void way station came under heavy assault by a Space Marine force later identified by their singular heraldry as belonging to the Celebrants Chapter. Objections were lodged at the highest possible levels of the Imperial hierarchy, but the Celebrants' Chapter Master dismissed the accusations as false and threatened reprisals if they were not retracted. The discord reached a climax when the Celebrants withdrew from joint anti-pirate operations in the Arataen Deeps, leading ultimately to the loss of three entire sub-sectors. Subsequent Ordo Hereticus investigations determined that the original attack was carried out by the Night Lords in a typically cunning ploy to sow terror and confusion amongst the defenders of the Imperium.
- Third War for Armageddon (998.M41) - The entire Celebrants Chapter participated in the Third War for Armageddon.
The Celebrants' Power Armour has a unique colour pattern, with yellow on the lower legs that seamlessly blends into orange for the mid-torso and then red for the upper torso, helmet and arms. The black squad specialty symbol -- Tactical, Assault, Devastator or Veteran -- is indicated on the right shoulder plate. A white Gothic numeral centred on the squad specialty symbol indicates squad number. The colour of the left knee guard indicates company number in accordance with the Codex Astartes -- i.e. White (1st Company), Yellow (2nd Company), Red (3rd Company), etc.
- Adeptus Astartes: Successor Chapters (Limited Release Booklet), pg. 23
- Codex: Armageddon (3rd Edition), pg. 32
- Hammer and Bolter 3, "The Long Games at Carcharias" by Rob Sanders
- Imperial Armour Volume Thirteen: War Machines of the Lost & The Damned, pg. 23
- Index Astartes: Emperor's Shield