In the United States since its early history, Native Americans, African-Americans and European-Americans were classified as belonging to different races. For nearly three centuries, the criteria for membership in these groups were similar, comprising a person’s appearance, his fraction of known non-White ancestry, and his social circle. But the criteria for membership in these races diverged in the late 19th century. During Post Civil War Reconstruction, increasing numbers of Americans began to consider anyone with “one drop” of known “black” blood to be black regardless of appearance. America’s “one-drop” rule is unique in world history as it only applies here in this country. According to Ross Nutt, (Creek descendant) “Native American people are the only people who are identified as a people by a variable degree of blood, and have cards (CDIB or Certificate of Degree of Indian or Alaska Native Blood) to identify the people as ‘qualified’ to be Indian.”

Homer Plessy was an “Octoroon,” a person having one-eighth black ancestry, who claimed his right to sit on white designated seats in Louisiana because he could pass for “White.” The Supreme Court’s “separate but equal” decision in Plessy v. Ferguson denied Mr. Plessy this right, thus recognizing the “one-drop” rule while legalizing Jim Crow segregation. Black Elk, a famous wičháša wakȟáŋ (medicine man and holy man) of the Oglala Lakota (Sioux) said, “ I am an Indian. If you have one drop of Indian blood in your veins, then you are Indian.” His statement encourages that the “rule” should not be fixed, but a choice for self-affirmation.

By the early 20th century, this notion of invisible blackness was made statutory in many states and widely adopted nationwide. In contrast, Amerindians continue to be defined by a certain percentage of “Indian blood” (called, blood quantum) due in large part to American slavery ethics.