Forerunner

The Forerunners were an ancient alliance of several extremely technologically advanced races whose combined empire encompassed several thousand fertile worlds across the breadth the Milky Way Galaxy. The Forerunners reigned for millennia as the ascendant civilization in the galaxy until the activation of the Halo Array, their Pyrrhic solution to halt the Flood.
== History ==
=== Origins ===
The various races that would be eventually known as Forerunners were created by the Precursors, a powerful race responsible for seeding the Milky Way Galaxy with life and creating many other species. The oldest of these races, the Isu, were seeded on Erde-Tyrene. The world served as the hub of the Isu's fledgling interstellar civilization. Eventually the Isu made first contact with the Praeleanthor civilization of neighboring Edom, saving them from extermination and enslavement at the hands of the Makyra.