Blood quantum

Blood quantum laws or Indian blood laws are those enacted in the United States and the former colonies to define qualification by ancestry as Native American, sometimes in relation to tribal membership. These laws were developed by Euro-Americans and thus did necessarily not reflect how Native Americans had traditionally identified themselves or members of their in-group, and thus ignored the Native American practices of absorbing other peoples by adoption, beginning with other Native Americans, and extending to children and young adults of European and African ancestry. Blood quantum laws also ignored tribal cultural continuity after tribes had absorbed such adoptees and mixed-race children.

A person's blood quantum (aka BQ) is defined as the percentage of their ancestors, out of their total ancestors, who are documented as full-blood Native Americans. For instance, a person who has one parent who is a full-blood Native American, and one who has no Native ancestry, has a blood quantum of 1/2. Since re-establishing self-government and asserting sovereignty, some tribes may use blood quantum as part of their requirements for membership or enrollment, often in combination with other criteria. For instance, the Omaha Nation requires a blood quantum of 1/4 Native American and descent from a registered ancestor for enrollment.

In 1705 the Colony of Virginia adopted laws that limited civil rights of Native Americans and persons of one-half or more Native American ancestry. The concept of blood quantum was not widely applied by the United States government until the Indian Reorganization Act of 1934. At that time, the government required persons to have a certain blood quantum in order to be recognized as Native American and to be eligible for financial and other benefits under treaties or sales of land.

Since that time, however, Native American nations have re-established their own governments, asserting sovereignty in setting their own rules for tribal membership, which vary among them. In some cases, individuals may qualify as tribal members, but not as American Indian for the purposes of certain federal benefits, which are still defined in relation to blood quantum. In the early 21st century some tribes tightened their membership rules and excluded persons who had previously been considered members, as have the Cherokee and Wampanoag. Challenges to such policies have been pursued by those excluded.

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