According to Pierce Brown, the Dark Revolt was caused by the Golds attempting to cull the massive Obsidian population down to more controllable numbers. There were many Obsidians bred for war during and before the Conquering, in order to use them as soldiers to conquer Earth. After the Golds successfully conquered Earth, the lingering population of Obsidians then had to find a place in The Society. Since Obsidians were restricted to roles involving war and combat (as guards, soldiers, etc.), the huge Obsidian population needed to be downsized in order to meet the shrunken demand of postbellum Society.
Little is known about the specifics of the conflict, but the Dark Revolt failed, resulting in the massacre of 90% of the Obsidian race. As a method of keeping the remaining Obsidians in check, the Board of Quality Control instituted Norse mythology among Obsidian tribes, restriction of technology, and strict rules regarding touching among Obsidians. Additionally, the vast majority of Obsidians not serving in The Society were constrained to the icy poles of planets such as Earth and Mars.