@Deleted User The one-drop rule is a social and legal principle of racial classification that was historically prominent in the United States asserting that any person with even one ancestor of sub-Saharan-African ancestry ("one drop" of black blood) is considered black (Negro in historical terms), its implications of racial purity being that anyone unable to pass for white in the context of the US racial hierarchy is assigned the lower status of being non-white or colored.
This concept evolved over the course of the 19th century and became codified into the law of some states in the early 20th century. It was associated with the principle of "invisible blackness" and 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.
The social and legal concept of the "one-drop rule" does not exist outside the United States. The "one-drop rule" is defunct in the United States and was never codified into federal law.
