Event · M32–M33
Fifth Founding
The Fifth Founding is one of the numbered creation waves through which the Adeptus Astartes raised new Chapters of Space Marines in the early Imperium. It followed the codification carried out under Roboute Guilliman, whose Second Founding split the loyalist Legions into approximately one thousand smaller Chapters governed by the Codex Astartes. Imperial record places the Fifth Founding within the thirty-second to thirty-third millennia, part of a sequence of periodic foundings by which the newly reorganised Astartes were replenished and expanded in the Imperium’s early centuries. Surviving Departmento Munitorum archives on Terra name few Chapters with certainty as products of the Fifth Founding, and later chroniclers’ accounts differ on which lineages it produced. What is attested is its place in a chain of foundings — the Second’s codification, then the Third and Fourth, and the Fifth in turn — each drawing gene-seed and warrior stock from the First Founding Legions to seed Chapters for war fronts opening across a galaxy still recovering from the Horus Heresy. As with other early foundings, its charters were sealed and administered from Terra, seat of the High Lords and the Adeptus Astartes’ governing bodies, binding the new Chapters into the Imperium’s chain of command even as they dispersed to fortress-monasteries far from Terra itself. The Fifth Founding is remembered today chiefly as a marker within the numbered sequence rather than as an event with a distinct narrative of its own, its specifics eclipsed by later, better-documented foundings such as the thirteenth, whose flawed gene-seed produced Chapters still contending with its legacy, and the foundings of the Badab War era nearer the present. Which Chapters serving in the present era trace their founding charter to the fifth wave remains uncertain, a gap Imperial record-keeping has never closed. The Founding nonetheless stands as one link in the continuous institutional history connecting the Great Crusade’s Legions, through Guilliman’s reforms, to the Chapters that defend the Imperium in the forty-first millennium.
See where Fifth Founding occurred on the galactic map in the 41st Millennium.