Inquisition (Warhammer 40,000)

The Inquisition (The Holy Orders of the Emperor's Inquisition) is an organization in the fictional Warhammer 40,000 universe. They act as the secret police of the Imperium, hunting down any and all threats to the stability of the God-Emperor's realm. In fiction relating to the games, Inquisitors are usually represented by extremely powerful, intelligent, and talented individuals. In the games, Inquisitors are usually powerful combatants with a variety of specialized abilities with a party of followers who improve and protect the Inquisitor. Inquisitors also grant the player access to many new units, such as Imperial Assassins and Daemonhosts.

In early editions of Warhammer 40,000, the Inquisition was a single, undivided organization, with a single inner order, the Ordo Malleus. The stated purpose of the Ordo was to police the Inquisition itself, but it also existed to combat the threat of the infinite hordes of Chaos. This massive war remains a secret hidden from most forces of the Imperium, including non-Malleus Inquisitors.

In later editions of Warhammer 40,000, the Inquisition is divided into three Ordos: Xenos, Malleus, and Hereticus, intended to combat threats to the Imperium from the activities of alien races, demons, and heretics, respectively. These Ordos act independently, and their agents sometimes come into conflict with each other.

The Ordo Xenos and Ordo Malleus both have specialized Space Marine chapters attached to them: the Deathwatch and the Grey Knights, respectively. Meanwhile, the Ordo Hereticus utilizes Orders drawn from the Sisters of Battle.

There are online rules for using the Deathwatch, the militant arm of the Ordo Xenos and one such Ordo Xenos Inquisitor has been released by Forge World. Following the end of the Inquisitor line, and the successful relaunch of Warhammer Fantasy Roleplay by Black Industries, it was decided that the first roleplaying game to explore the Warhammer 40,000 universe would be Dark Heresy, a game in which the player characters are, by default, diverse agents of the Inquisition sent to investigate various mysteries and heresies on behalf of their Inquisitor.

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Wikipedia