Plessy v. Ferguson was a landmark U.S. Supreme Court case decided in 1896. The case centered around Homer Plessy, a man of mixed racial heritage who was arrested for refusing to leave a whites-only railway car in Louisiana. Plessy argued that the state law segregating railway facilities based on race violated his rights under the 14th Amendment to the U.S. Constitution, which guarantees equal protection under the law.

However, in a 7-1 decision, the Supreme Court upheld the Louisiana law and established the "separate but equal" doctrine. This ruling essentially legalized racial segregation by allowing for separate facilities for Black and white individuals as long as they were deemed to be equal in quality. The decision in Plessy v. Ferguson had wide-reaching consequences and provided a legal basis for racial segregation in various aspects of American society, laying the groundwork for decades of institutionalized racism and discrimination.

Plessy v. Ferguson remained the law of the land until it was overturned by the Supreme Court in the landmark case Brown v. Board of Education in 1954, which declared that separate educational facilities are inherently unequal and unconstitutional.