Event · M31

First Black Crusade

The First Black Crusade opened with the First Battle of Cadia in 781.M31. Sigismund, High Marshal of the Black Templars, had maintained a fleet at the Cadian Gate against renewed incursion by the forces of Chaos, a watch kept in anticipation of exactly the attack that followed. When Abaddon brought the Black Legion to Cadia, he left the Vengeful Spirit under the command of the sorcerer Iskandar Khayon and boarded Sigismund’s flagship, the Eternal Crusader, in person, rather than direct the battle from his own vessel. There he sought to persuade Sigismund to abandon the Imperium and join him in the Long War; Sigismund refused, and the two fought. Sigismund was killed in the duel, but not before driving his Black Sword into Abaddon’s chest, a wound from which Abaddon barely survived. During the wider fleet battle, Abaddon’s rival Thagus Daravek arrived at Cadia with the Legion Host, and Khayon killed Daravek. Much of the Black Legion escaped into the warp rather than press the attack to destruction. The Black Legion then sent the captured ship Valorous Vow to Terra bearing Sigismund’s body, and Khayon cut the words “We are returned” into the Black Sword before it was sent, a message meant for the Imperium that had cast the Traitor Legions out. The war that followed ran for decades across the Segmentum Obscurus, far outlasting the single battle that had opened it. Cadia itself, not yet the heavily fortified bastion it would later become, held against the Black Legion’s repeated assaults. On the world of Urthwart, Cadian troops together with the 4th and 5th Companies of the Imperial Fists held for four days against an attack in which the first Defiler war engines were used against the Imperium, the attackers eventually withdrew without taking the world. Imperial forces gradually reclaimed lost territory across the following decades and drove Abaddon back from the gains he had made. In the war’s aftermath, the Imperium raised extensive new defences on Cadia itself and established a naval port at Belis Corona to guard the approaches to the Cadian Gate. The First Black Crusade is recorded as an Imperial pyrrhic victory: Cadia held, and the Black Legion was driven back, but at great and lasting cost to the Imperial forces that had defended it. On Uralan, during the same crusade, Abaddon claimed the daemon sword Drach’nyen from the Tower of Silence. One account dates that claim to 781.M31, the year the crusade opened. The narrative of the crusade places it instead at the end of the decades-long war, after Cadia had been fought over many times. Both dates are recorded, and neither is preferred. The opening of the crusade itself remains 781.M31. Cadia held, Sigismund was killed, and the sword was taken; the record does not treat the withdrawal as a campaign in which nothing was achieved. During the crusade he also drew former Sons of Horus warbands into the Black Legion, notably the Sons of the Eye, and other exiles of the Traitor Legions were permitted to join its ranks.

See where First Black Crusade occurred on the galactic map during the Horus Heresy.

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