Event · M41–M42
Indomitus Crusade Fleet Tertius
Indomitus Crusade Fleet Tertius was one of the crusade fleets mustered at Terra after the Cicatrix Maledictum opened in 999.M41. The tearing of that warp-rift across the galaxy’s heart, following the fall of Cadia, split the Imperium into the Imperium Sanctus and the Imperium Nihilus and left entire sectors cut off from Terra’s authority. In response, the Adeptus Terra assembled the Indomitus Crusade under Roboute Guilliman, the newly returned Primarch of the Ultramarines, drawing on the first companies of Primaris Space Marines created through Belisarius Cawl’s Ultima Founding; Fleet Tertius was raised within this general mobilisation as one of the numbered battle fleets despatched from Terra to carry reinforcement and relief to threatened sectors of the Imperium Sanctus. The fleet’s specific theatre and campaign record are less consistently attested than those of the Indomitus Crusade’s better-chronicled formations, and accounts differ on the precise worlds it relieved and the forces it fought alongside. What is recorded places it firmly within the Crusade’s wider pattern: convoys of Primaris reinforcements, war matériel, and newly raised companies moving out along the crusade’s routes to shore up garrisons weakened by the Cicatrix Maledictum’s opening, coordinating where possible with sector fleets, Astra Militarum commands, and Space Marine Chapters holding the line against the threats loosed by the Rift. Its operations fall within the same span, 999.M41 to 999.M42, that saw Guilliman direct the Crusade’s main strength from Terra and later from Ultramar. By the time the Indomitus Crusade was formally concluded, its numbered fleets, Tertius among them, had been absorbed into the standing garrisons, Chapters, and sector commands they had reinforced, their Primaris strength dispersed into the Imperium’s permanent order of battle rather than retained as a standing crusade force. Fleet Tertius is remembered, where it is remembered at all, as one contributor among many to the Imperium Sanctus’s survival in the era after the Rift, its story bound to Terra as mustering point, to Guilliman as the Crusade’s architect, and to the broader Indomitus Crusade of which it formed one thread.
See where Indomitus Crusade Fleet Tertius occurred on the galactic map in the 41st Millennium.