The Nova Terra Interregnum, also known as the "Time of Twin Empires," was a troubled period in Imperial history when the Imperium of Man fractured for a time into warring factions for over 900 standard years during the mid-34th through the late-35th Millennium. During this period, the rebellious Ur-Council of Nova Terra dismissed the authority of the High Lords of Terra and claimed separate rule over the Imperium's Segmentum Pacificus.
There exists in what records remain from this tumultuous era scattered and veiled references to a great threat to Mankind arising in the Ghoul Stars known as the Pale Wasting. Much of the extant evidence relating to this threat has been censored or purposely destroyed, but there are contradictory indications which describe the nature of the threat as both a "Star-spawned plague" that swept away scores of worlds and to "Nightmare Engines" that slaughtered the populations of whole sectors. The Novamarines Space Marine Chapter took part in the campaign to quell the threat of the Pale Wasting, and though this is one of the Chapter's earliest recorded battle honours, the Chapter's own chronicles are curiously empty of any reference to this conflict. Stationed beyond the frontiers of the Imperium, the Death Spectres Space Marine Chapter currently maintains a constant vigil to ensure that the inhabitants of the Ghoul Stars never again threaten the galaxy.
After almost a millennium of low-grade civil war and political maneuvering, the Cataclysm of Souls in 975.M35 reunited the Imperium. In that year, the Ecclesiarchy tried to transform the Imperium into a theocracy and usurp the power of the rest of the High Lords of Terra. Their efforts ended only in stirring up massive religious civil wars against the Ur-Council who were denounced as Heretics who stood in defiance of the will of the God-Emperor when they rejected the Ecclesiarchy's attempts to increase its power over the state. This religious rebellion on many worlds of the Segmentum Pacificus ultimately overthrew the Ur-Council and restored the rule of the High Lords over the entirety of the Imperium's territory, though the power of the Ecclesiarchy had been dramatically increased throughout the Imperium as a result.
- The Pale Wasting (Unknown Date.M34) - A stele mounted within the Imperial Palace on Terra recognises the services of the Novamarines for their action against the Pale Wasting that occurred in the 34th Millennium. This artefact praises the Chapter and credits their work for having "unmade that which cannot die." This campaign was where the Novamarines earned some of their earliest recorded battle honours. During the dark and terrible times known to later historians as the Nova Terra Interregnum, when the Imperium fractured into warrior factions during this tumultuous period, there exists in what records remain from this era scattered and veiled references to a great threat arising from the Ghoul Stars. Much of the extant evidence relating to this threat has been censored or purposely destroyed, but there are contradictory indications which describe the nature of the threat as both a "star-spawned plague" that swept away scores of worlds and as "nightmare engines" slaughtering whole sectors. Those partial records which have been uncovered suggest that the threat was xenos in nature and that more than one Space Marine Chapter may have been completely destroyed in the course of the conflict. The Novamarines took part in the campaign to quell the threat of the Pale Wasting, and though this is one of the Chapter's earliest recorded battle honours, the Chapter's own chronicles are curiously empty of any reference to this conflict. Were it not for such prominent recognition, the incident might be completely forgotten.
- The Moirae Schism (Unknown Date.M35) - During the dark days of the Nova Terra Interregnum, this conflict tears apart the Adeptus Mechanicus, dividing the Machine Cult in a way unseen since the Horus Heresy. Known as the Moirae Schism, the servants of the Cult Mechanicus were split in two by a doctrine that claimed to be able to read the future in minute fluctuations in the blessed Astronomican. Furthermore, the future the schismatics read in the wave functions spoke of a future age in which the Cult Mechanicus and the Ecclesiarchy were merged as one unified creed adhered to by the entire Imperium. Needless to say, neither body would countenance such a thing and internecine war soon split the Adeptus Mechanicus in two. As a result, the Forge World of Moirae is blasted to dust, but not before the schism spreads throughout the Cult of Mars, the Titan Legions and several Space Marine Chapters with close ties to the Adeptus Mechanicus. Over two thousand years of bloody strife pass before the baleful doctrine is considered fully purged.
- Raid on Nova Terra (257.M35) - The Dark Angels, following the trail Cypher, are led to believe that at least one member of the newly declared Ur-Council of Nova Terra is the notorious Fallen Angel. A daring Ravenwing strike assaults Nova Terra, but fails to apprehend any prisoners.
- Hrakon Campaign (495.M35) - The Segmentum Pacificus is the centre of unrest during the Nova Terra Interregnum and the Dark Angels Chapter's Inner Circle continues to follow the many clues that have led them deep into the internecine fighting in the region. Known to the Dark Angels as the Hrakon Campaign, they systematically seek out Obidiah Hrakon, the despot ruler of an upstart planet which has been pivotal in its support of Nova Terra. In the Veiled Region, the Dark Angels finally corner Hrakon, who takes refuge on a piratical port world. Seeking to ensure that none escape, the Dark Angels blockade the planet and unleash the entire Deathwing. Deploying in sequential teleportations, the Terminators prosecute an epic slaughter until only a single foe is left alive -- Obidiah Hrakon -- once a Standard Bearer for the ancient Dark Angels Legion. Refusing to give up, Obidiah is subdued after a duel with the Grand Master of the Deathwing and is transported back to The Rock to face the tender mercies of the Interrogator-Chaplains. His death is not an easy one.
- Cataclysm of Souls (975.M35) - The Ecclesiarchy begins to rebind the sundered Imperium as a religious state that transcends political differences. Billions die in the religious wars when the Ur-council of Nova Terra rejects the Ecclesiarchy's teachings. It is a civil war the likes of which the Imperium has not seen since the Horus Heresy.
- Codex: Dark Angels (6th Edition), pg. 23
- Codex: Skitarii (7th Edition), pg. 36
- Dataslate: Cypher - Lord of the Fallen, pg. 29
- Imperial Armour Volume Nine - The Badab War - Part One, pg. 118
- Warhammer 40,000 Rulebook (6th Edition), pg. 170
- Warhammer 40,000 Rulebook (5th Edition), pp. 124-125