The High Lords of Terra were a mortal government established by the Emperor toward the end of the Great Crusade, composed of twelve individuals who held supreme authority in their respective spheres.
There were nine permanent seats, namely:
The Master of the Administratum: the official who oversaw the Imperium's entire Department of the Interior, responsible for the Imperial Tithe and the Imperium's domestic affairs.
The Ecclesiarch of the Adeptus Ministorum: the supreme authority of the Ecclesiarchy, serving only the Emperor.
The Fabricator-General of the Adeptus Mechanicus: generally the Fabricator-General of Mars, as the Fabricator-Generals of other Forge Worlds could rarely challenge Mars's authority.
The Grand Provost Marshal of the Adeptus Arbites: the supreme authority of the Imperium's Adeptus Arbites, responsible for enforcing Imperial law and making necessary revisions.
The Paternoval Envoy of the Navigators: the representative dispatched by the Navigator houses.
The Master of the Astronomican Court: the representative dispatched by the Astronomican Court.
The Grand Master of the Officio Assassinorum: the leader of the Officio Assassinorum, responsible for hunting down and assassinating threats as necessary.
The Master of the Adeptus Astra Telepathica: the representative dispatched by the Adeptus Astra Telepathica.
The Representative of the Inquisition: the Inquisition's representative, whose duties were more concerned with maintaining stability in the Solar System.
The remaining three were nonpermanent seats, including relics of the Great Crusade such as the Solar Commander and the Captain-General of the Adeptus Custodes, as well as later additions such as the Canoness Superior.
It could not be denied that the High Lords of Terra had played an important role in stabilizing the Imperium after the Emperor took his seat upon the Golden Throne, just as the Ecclesiarchy had become a new source of spiritual support afterward.
But it also had to be understood that, after the first generation