"Separate but equal" was a legal doctrine in the United States that allowed for racial segregation under the law, particularly in the South, following the end of Reconstruction in the late 19th century. This doctrine was established by the Supreme Court case Plessy v. Ferguson in 1896, which upheld state segregation laws as long as the separate facilities provided for Black and white individuals were deemed to be "equal."

However, in reality, the facilities for Black individuals were almost always inferior to those for white individuals, perpetuating systemic racism and inequality. This doctrine of "separate but equal" was used to justify segregation in all aspects of society, from public schools and transportation to housing and public facilities, effectively institutionalizing racial discrimination.

The civil rights movement of the 1950s and 1960s sought to challenge and dismantle the "separate but equal" doctrine, culminating in the landmark Supreme Court case Brown v. Board of Education in 1954, which declared state laws establishing separate public schools for Black and white students to be unconstitutional. This decision marked a significant turning point in the fight against segregation and racial discrimination in the United States.