Desegregation is the process of ending the separation of two groups, usually referring to races. Desegregation is typically measured by the index of dissimilarity, allowing researchers to determine whether desegregation efforts are having impact on the settlement patterns of various groups. This is most commonly used in reference to the United States. Desegregation was long a focus of the American civil rights movement, both before and after the US Supreme Court's decision in Brown v. Board of Education, particularly desegregation of the school systems and the military. Racial integration of society was a closely related goal.

The civil rights movement was a social movement and campaign from 1954 to 1968 in the United States to abolish legalized racial segregation, discrimination, and disenfranchisement in the country. The movement had its origins in the Reconstruction era during the late 19th century and had its modern roots in the 1940s, although the movement made its largest legislative gains in the 1960s after years of direct actions and grassroots protests. The social movement's major nonviolent resistance and civil disobedience campaigns eventually secured new protections in federal law for the civil rights of all Americans.