Gallifreyan Empire

The Gallifreyan Empire was a brutal star-spanning empire of Ancient Gallifreyans ruled by the Pythian Order starting in the Time of Empire of the Age of the Pythias. Gallifrey was the empire's origin and hub, with large fleets of spaceships led by Gallifreyan Heroes leaving it to expand the outer edges of the empire. It was economically reliant on a slave trade, with aliens often taken back to Gallifrey to compete in the games of the Death Zone. (PROSE: Cat's Cradle: Time's Crucible)

The Empire encompassed the Pen-Shoza, Jagdagian, Oshakarm, the Star Grellades, Mirphak 2, the rebellious Aubert Cluster, and Tersurus. (PROSE: Cat's Cradle: Time's Crucible, A History of the Universe) By some accounts, the Vampire war was fought by the Gallifreyan Empire. (PROSE: Lungbarrow, Gallifrey - Notes on the Planet's Background)

The Empire withered and collapsed following the Intuitive Revelation, with Gallifrey becoming more isolated in the years following Pythia's Curse. (PROSE: Cat's Cradle: Time's Crucible) During the violence surrounding the purge of Pythia's Temple, the Capitol's spacedrome was destroyed, further isolating Gallifrey from the outside universe. (PROSE: Lungbarrow) Ruins of the empire still existed on Gallifrey's surface, but were covered by the Gallifreyan Ice Age. (PROSE: The Infinity Doctors)

A different yet somewhat similar account indicated that the Time Lords were preceded by a space-faring militaristic culture called the Space Lords. (COMIC: Monstrous Beauty)