The one-drop rule was a legal principle of racial classification that was prominent in the 20th-century United States. It asserted that any person with even one ancestor of black ancestry is considered black. It is an example of hypodescent, the automatic assignment of children of a mixed union between different socioeconomic or ethnic groups to the group with the lower status, regardless of proportion of ancestry in different groups.
Rice and Powell (on the left) are considered black in the US. Bush and Rumsfeld (on the right) are considered white.
Lena Horne was reportedly descended from the John C. Calhoun family, and both sides of her family were a mixture of African-American, Native American, and European American descent.
A Redenção de Cam (Redemption of Ham), by Galician painter Modesto Brocos, 1895, Museu Nacional de Belas Artes. The painting depicts a black grandmother, mulatta mother, white father and their quadroon child, hence three generations of hypergamy through racial whitening.
The Bogdanoff brothers are not considered black in France, with few people even aware of their African ancestry. In the U.S, they would be black as a result of the one-drop rule.
Race (human categorization)
Race is a categorization of humans based on shared physical or social qualities into groups generally viewed as distinct within a given society. The term came into common usage during the 16th century, when it was used to refer to groups of various kinds, including those characterized by close kinship relations. By the 17th century, the term began to refer to physical (phenotypical) traits, and then later to national affiliations. Modern science regards race as a social construct, an identity which is assigned based on rules made by society. While partly based on physical similarities within groups, race does not have an inherent physical or biological meaning. The concept of race is foundational to racism, the belief that humans can be divided based on the superiority of one race over another.
The "three great races" according to Meyers Konversations-Lexikon of 1885–90. The subtypes are: Mongoloid race, shown in yellow and orange tones Caucasoid race, in light and medium grayish spring green-cyan tones Negroid race, in brown tones Dravidians and Sinhalese, in olive green and their classification is described as uncertain The Mongoloid race sees the widest geographic distribution, including all of the Americas, North Asia, East Asia, Southeast Asia, and the entire inhabited
"Races humaines" according to Pierre Foncins La deuxième année de géographie of 1888. White race, shown in rose, Yellow (Mongoloid) race, shown in yellow, Negroid race, shown in brown, "Secondary races" (Indigenous peoples of the Americas, Australian aboriginals, Samoyedic peoples, Hungarians, Malayans and others) are shown in orange
Portrait "Redenção de Cam" (1895), showing a Brazilian family becoming "whiter" each generation