In the fictional Warhammer 40,000 universe a Black Crusade is when the forces of Chaos manage to unite under a particularly strong leader and go forth en'masse to wage war against the Imperium of Man. There has been thirteen Black Crusades to date, all started by Abbadon, Warmaster of the Black Legion and the (rumoured) clone-son of Horus. The 13th Black Crusade was the backgrond to the world-wide Warhammer 40,000 Eye of Terror campaign, which resulted in a minor victory for the forces of Chaos. As of the 4th edition rules, Humanity is truly imperiled, having been forced another step back into the abyss.

Prior to the 13th Black Crusade, each of Abbadon the Despoiler 's 12 assaults on the Imperium had failed. Now however, having gained a foothold on the Cadian system, he is able to strike out and attack from real space , as opposed to traversing the Immaterium .