This page is dedicated in remembrance of all those Space Marine Chapters that are entirely and definitely very dead. This does not include chapters that fell to Chaos, so all those lost (wiped out, turned heretic, barely survived or still missing) during the Abyssal Crusade aren't listed here, for that see Judged. Special mentions to the 2 lost legions.
Seriously, don't put crimson in the chapter's title if you want it to live. This chapter was taken out piece by piece in a series of freak accidents which were only discovered to have been arranged by the Alpha Legion when their battle-brothers' subliminal programming was activated to wipe out the Chapter leadership.
Annihilated by Necrons while investigating Jarrman Prime.
Destroyed by the Alpha Legion who contaminated their recruiting pool and implanted subconscious triggers in their recruits.
Emperor's Swords againEdit
Based on Bellicas, which turned out to be a tomb world. Begin face-palming.
Discretely replaced the completely depleted Imperial Fists with a handful of other volunteers from the Imperial Fists' successors after The War of The Beast, with their records purged after it was discovered that the remaining members of the chapter had detected to the Iron Warriors.
Declared excommunicate traitoris by the Inquisition and officially extinguished by Grey Knights. Few survived.
Destroyed in War of The Beast, secretly replenished with Fists Exemplar.
Knights of BloodEdit
Knights of EternityEdit
Another chapter presumed to have been eaten by the Kraken.
Chapter destroyed by the Red Waagh. Detailed in Sanctus Reach campaign.
Extinct by M41. Refounded to replace Astral Knights.
Fought along with the Black Templars defending their homeworld against a hive fleet. Notable for dying to a man with the last to fall being a battle brother keeping the chapter banner aloft; hardcore.
Declared extinct. After becoming disillusioned with the Imperium and turning renegade, they were finally brought to trial and ended up sacrificing themselves to fend off a daemon army, the three loyalist survivors exhiled themselves to the warp along with their Chaos turned brother.
The initial reserve of Primaris Marines before they were entirely reorganised into existing chapters or formed new or legacy chapters. Not technically extinct, but no longer exists as a functioning unit.
Succumbed to the instabilities of their gene-seeds. Any survivors are now feral wulfen.