	Over the centuries when Whites wielded power over both Blacks and Amerindians and believed in their inherent superiority over people of color, they created a social order of hypodescent, in which they assigned mixed-race children to the lower-status groups. They were often ignorant of the systems among Native American tribes of social classification, including kinship and hypodescent. The Omaha people, for instance, who had a patrilineal kinship system, classified all children with white fathers as "white", and excluded them as members of the clans and tribe, unless one was formally adopted by a male member. Tribal members might care for mixed-race children of white fathers, but considered them outside the hereditary clan and kinship fundamental to tribal society.