Frequently called integration by its observers, desegregation originated before World War II and continued with mixed progress through the Second Reconstruction (1945–1982) to the present. Black activism, which prodded federal steps to end “separate but equal” in law and practice,” evinced four stages: early, emergence, expansion, and impasse.

Early challenges to Jim Crow included the antilynching, voting rights, and equalization campaigns. NAACP suits to equalize schools, teachers’ salaries, graduate and professional school, suffrage, and economic opportunity (1930–44) mirrored ongoing African American movements against lynching, disfranchisement, job discrimination, and unequal education. A black applicant won admission to the all-white University of Maryland Law School (1936) and another to the University of Missouri Law School (1938). Executive Order 8802 created the Fair Employment Practices Committee (1941), averting blacks’ march on Washington for jobs and freedom. Black churches and organizations mobilized to support Smith v. Allwright (1944), the Texas case in which the Supreme Court outlawed the “white primary” election.

In the wake of Smith, more than a million southern blacks registered to vote and the movement for racial justice emerged (1945–54). It influenced the President's Committee on Civil Rights, whose 1947 report proposed laws repealing the poll tax, lynching, and segregated transportation. The president also issued an order to desegregate US Armed Forces (1948). Black applicants were admitted to seven state universities by Federal Court orders and to two voluntarily (1948–51). Segregated school cases culminated in Brown v. Board of Education (1954), which declared “separate educational facilities ... inherently unequal.”

Brown leveraged civil rights. The Montgomery Bus Boycott (1955) and Little Rock School Crisis (1957) reflected the movement's push to open society. Using nonviolent direct action, black activists and their allies struggled to desegregate education, employment, public accommodations, and more. The shameful international publicity resulting from racist violence during sit-ins, Freedom Rides, and the Birmingham and Selma protests pressured Congress to pass the Civil Rights Act (1964) and Voting Rights Act (1965). At the time, only 2.3 percent of black children attended former white schools and 55 percent of blacks were poor.

Desegregation proceeded, but conservative opposition slowed it. While the Federal Courts in 1968 disallowed freedom-of-choice plans to end school segregation and, by 1971, ordered busing students, “white flight” produced private schools, suburban school districts, and anti-busing politics. Simultaneously, educational and family assistance programs of the War on Poverty helped to reduce African American poverty to 30.3 percent by 1974.