Event · M36
Seventeenth Founding
The Seventeenth Founding is one of the numbered foundings by which the Adeptus Terra raised new Chapters of the Adeptus Astartes from reserved gene-seed. Foundings of this kind descend from the precedent set by the Second Founding, when Roboute Guilliman’s Codex Astartes broke the old Legions into smaller, self-contained Chapters; thereafter the High Lords of Terra sanctioned further foundings at intervals to replenish losses and extend the Adeptus Astartes into regions of the Imperium that lacked a standing Chapter. The order to proceed, the selection of gene-seed stocks, and the appointment of a founding Chapter Master were all matters administered from Terra, which stands as the founding’s point of origin in Imperial record even where the Chapters it produced were despatched to serve far from Holy Terra itself. No single crisis is recorded as having prompted the Seventeenth Founding; Imperial chronicles instead place it among the piecemeal renewals carried out by the Adeptus Terra and the Adeptus Mechanicus across the centuries following Guilliman’s reforms, each founding drawing on tithed gene-seed and newly built fortress-monasteries to bring a Chapter to readiness before it was assigned a home world and a war footing. Accounts differ on how many Chapters trace their lineage to this particular founding, and later tradition holds that its administrative record was never as fully preserved as those of the more celebrated foundings, such as the Second or the Cursed Founding. What survives of the Seventeenth Founding today does so chiefly as fragmentary entries in the Chapter rolls kept on Terra, cited by archivists seeking to place a Chapter’s age and gene-seed lineage within the broader sequence of foundings rather than as a self-contained campaign or war. Its significance lies in that sequence itself: as a fixed point in Astartes chronology, it helps anchor the relative age of the Chapters attributed to it against the Second Founding before it and the later, better-documented foundings that followed.
See where Seventeenth Founding occurred on the galactic map in the 41st Millennium.