The Wars of Apostasy or the Terran Crusade was a series of battles and military campaigns fought against the forces of the Renegade High Lord of Terra Goge Vandire during the Age of Apostasy's Reign of Blood in the fourth century of the 36th Millennium by the Emperor of Mankind's Loyalists. During this tumultuous period, the Black Templars had concerned themselves little with the affairs of the Imperium, but when Crusade fleets returned to the Segmentum Solar and discovered that their Chapter keeps had been destroyed by orbital bombardments, the full extent of Vandire's treachery became apparent. Enraged by what they discovered of Vandire's perversion of the Emperor's will, in 378.M36 the Black Templars Chapter's High Marshal Sigenandus declared a Crusade to be launched against Vandire on Terra. The Black Templars, together with their progenitors the Imperial Fists, the Soul Drinkers, the zealous Fire Hawks and elements of the Martian Tech Guard, took the fight to Terra itself and laid siege to Vandire's Ecclesiarchal Palace.
For months the armies of the Imperial preacher Sebastian Thor, the Space Marines and their allies laid siege to the Ecclesiarchal Palace without managing to breach its formidable defences. Eventually, a forlorn hope led by the Emperor's Champion Navarre of the Black Templars led a daring last ditch assault. At the height of the fighting, the Chapter Banner Bearer fell, and all eyes watched as the Black Templars Chapter Standard began to slowly sink to the ground, but Navarre swept the banner up and carried it through the breach in the palace's walls, inspiring his brothers to fight all the harder. After the battle, Chapter Master Lazerian of the Imperial Fists honoured Navarre with the title of Captain of the Banner in recognition of his exemplary bravery and courage.
With the outer walls breached, the loyal warriors of the Emperor carried the fighting into the inner precincts of the Ecclesiarchal Palace, a violation of Terra's surface by an armed force that had not happened since the dark days of the Horus Heresy when the Imperial Fists and Blood Angels Legions had stoically held the Traitors at bay. The situation was now reversed, but despite the prowess of the Space Marines and their allies the overall fighting was brutal and ugly. The fighting only came to an end when a Centurion of the Companions of the Emperor's personal bodyguard -- the Adeptus Custodes -- made the rare decision to leave the Imperial Palace and intervene in the conflict. He brought Alicia Dominica, the leader of the militant Sisterhood known as the Brides of the Emperor who served as Goge Vandire's own fervently loyal protectors, through ancient and secret passageways known only to the Custodes. The Centurion, Dominica and her bodyguard of five female warriors (Arabella, Katherine, Lucia, Mina, and Silvana) moved through these ancient byways from the Ecclesiarchal Palace to the Imperial Palace. Once beyond the Eternity Gate and within the Inner Palace, Dominica and her retinue was granted an audience before the Golden Throne itself.
The Brides of the Emperor was a militant sect of nuns that Goge Vandire had enlisted as his strong arm, equipped with holy Bolters and cleansing Flamers, and armored in sanctified Power Armor the Brides were a formidable force to be reckoned with, but it was their faith from which they drew their true power. No one knows what transpired within the Emperor's Throne Room, but when Dominica emerged she and a cadre of her most trusted companions marched straight to Vandire's audience chamber, denouncing him as a Heretic and a Traitor. Dominica then drew her Power Sword and cleaved his head from his shoulders, ending the Wars of Apostasy and Vandire's Reign of Blood in one fell swoop. Sebastian Thor became the newly appointed Ecclesiarch, and the renamed Daughters of the Emperor became the Adepta Sororitas, the militant arm of the Ecclesiarchy and the Chamber Militant of the newborn Ordo Hereticus, the arm of the Inquisition tasked with preventing another member of the Imperial elite from ever again turning the organs of the Imperium against the will of the Emperor. The victorious Space Marines departed, their mission complete. It is unknown, however, whether the Black Templars rebuilt their Chapter Keeps within the Sol System, or whether they moved on immediately.
- Codex: Black Templars (4th Edition), pg. 19
- White Dwarf 312 (UK), "Righteous Victories" by Graham McNeill, pg. 22
- Daenyathos (Novella) by Ben Counter