Brown v. Board of Education of Topeka, 347 U.S. 483 (1954), was a landmark decision by the U.S. Supreme Court, which ruled that U.S. state laws establishing racial segregation in public schools are unconstitutional, even if the segregated schools are otherwise equal in quality. The decision partially overruled the Court's 1896 decision Plessy v. Ferguson, which had held that racial segregation laws did not violate the U.S. Constitution as long as the facilities for each race were equal in quality, a doctrine that had come to be known as "separate but equal".The Court's decision in Brown paved the way for integration and was a major victory of the civil rights movement, and a model for many future impact litigation cases.

The underlying case began in 1951 when the public school system in Topeka, Kansas, refused to enroll local black resident Oliver Brown's daughter at the elementary school closest to their home, instead requiring her to ride a bus to a segregated black school farther away. The Browns and twelve other local black families in similar situations filed a class-action lawsuit in U.S. federal court against the Topeka Board of Education, alleging that its segregation policy was unconstitutional. A special three-judge court of the U.S. District Court for the District of Kansas rendered a verdict against the Browns, relying on the precedent of Plessy v. Ferguson and its "separate but equal" doctrine. The Browns, represented by NAACP chief counsel Thurgood Marshall, then appealed the ruling directly to the Supreme Court.

In May 1954, the Supreme Court issued a unanimous 9–0 decision in favor of the Browns. The Court ruled that "separate educational facilities are inherently unequal", and therefore laws that impose them violate the Equal Protection Clause of the Fourteenth Amendment of the U.S. Constitution. However, the decision's 14 pages did not spell out any sort of method for ending racial segregation in schools, and the Court's second decision in Brown II (349 U.S. 294 (1955)) only ordered states to desegregate "with all deliberate speed".

In the Southern United States, especially the "Deep South", where racial segregation was deeply entrenched, the reaction to Brown among most white people was "noisy and stubborn". Many Southern governmental and political leaders embraced a plan known as "Massive Resistance", created by Virginia Senator Harry F. Byrd, in order to frustrate attempts to force them to de-segregate their school systems. Four years later, in the case of Cooper v. Aaron, the Court reaffirmed its ruling in Brown, and explicitly stated that state officials and legislators had no power to nullify its ruling.
Summarize Brown vs. Board of Education of Topeka in one sentence.
Brown vs. the Board of Education of Topeka was a unanimous 1954 ruling by the U.S. Supreme Court that racial segregation in U.S. public schools was unconstitutional, which paved the way for civil rights and racial integration.