Malreppidar, based in the Core of the Milky Way, controlled not only every known galaxy in our universe, but also a vast majority of those in the Secondary Spaces.
Population: Malreppidar may have ruled over septillions
Type: Theocratic totalistarianism
Administrative divisions: Unknown and possibly inconceivable
Leadership: The Gergathan ruled Malreppidar, directly and through copies of itself established in various Secondary Spaces.
Religions: Worship of the Gargathan as ultimate god is conjectured.
Language analog: Old Chinese
After the fall of Avethell, the Gergathan proclaimed Malreppidar, and began the systematic destruction of all life in other galaxies. Before this effort was really begun, about 3 million BCE, intercontinuual travel was developed, and Malreppidar spread like a virulent plague into the Secondary Spaces. (The Deserted Worlds of the New Continuum date from this era.)
About 2.7 million BCE, a tributary state in an adjacent continuum revolted and seriously damaged the Gergathan. Malreppidar fell.
The Kohlenebian Empire carried on the Core culture in the Scattered Worlds, but a true successor to Malreppidar did not appear until about 900,000 BCE, with Kaypleskrit.