Many things influenced the changes in U.S. race relations after World War II. The anti-Nazi propaganda generated during the war increased the realization by many Americans of the conflict between ideals and the reality of racism in their own country. The concentration of large numbers of blacks in cities of the North and West increased their potential for political influence. It also projected the problems related to race as national rather than regional. The establishment of the United Nations headquarters in the United States made American racial inequality more visible to a world in which the United States sought to give leadership during the cold war with the USSR. The growth of a white minority willing to speak out against racism provided allies for African Americans. Most important in altering race relations in the United States, however, were the actions of blacks themselves.

Legal Action against Racism. The first major attack by African Americans on racism was through the courts. In a series of cases involving professional and graduate education, the Supreme Court required admission of blacks to formerly all-white institutions when separate facilities for blacks were clearly not equal. The major legal breakthrough came in 1954. In the case of Brown v. Board of Education of Topeka, Kansas, the Supreme Court held that separate facilities are, by their very nature, unequal. In spite of this decision, more than a decade passed before significant school integration took place in the South. In the North, where segregated schools resulted from segregated housing patterns and from manipulation of school attendance boundaries, separation of races in public schools increased after 1954. A second major breakthrough in the fight against segregation grew out of the Montgomery, Ala., bus boycott in 1955. The boycott began when Rosa Parks, an African American woman, refused to give up her seat on the bus to a white person. Her arrest resulted in a series of meetings of blacks in Montgomery and a boycott of buses on which racial segregation was practiced. The boycott, which lasted for more than a year, was almost 100% effective. Before the courts declared unconstitutional Montgomery's law requiring segregation on buses, Martin Luther King, Jr., a Baptist minister, had risen to national prominence and had articulated a strategy of nonviolent direct action in the movement for civil rights.

Nonviolent Direct Action. Nonviolent direct action, born in the boycott, was taken up by blacks and white supporters throughout the country. It was applied by those who participated in sit-ins and the Freedom Riders, who sought to end segregation in public places. Protest demonstrations of all kinds were widespread. Among these were the March on Washington of Aug. 28, 1963, in which more than 200,000 blacks and whites protested continued segregation and discrimination, and large-scale demonstrations in Birmingham, Ala. (April 1963), and Selma, Ala. (March 1965). These civil rights activities were directed by long-established groups such as the NAACP and CORE (the Congress of Racial Equality, founded 1942), by newly formed national groups such as the Southern Christian Leadership Conference and SNCC (the Student Non-violent Coordinating Committee), and by such local groups as the Dallas County (Ala.) Voters League and the Princeton (N.J.) Association for Human Rights. The response of segregationists to the demonstrations was to blame outside agitators for causing the trouble. Many law officials took strong, often brutal measures to halt demonstrations or else refused to protect the right of demonstrators to protest peacefully.

Violence against black and white civil rights activists was commonplace. Three civil rights workers were brutally murdered in Philadelphia, Miss., in 1964; four African American children were murdered in the bombing of the 16th Street Baptist Church in Birmingham in 1963; and dozens of black churches throughout the South were burned or bombed. Two whites and one black were murdered during the 1965 demonstrations in Selma, Ala. In 1968, Martin Luther King, Jr., the recognized leader of the civil rights movement, was assassinated.

The federal response to the violent reaction of segregationists was the passage of several new laws, the most important of which were enacted in 1964 and 1965. The Civil Rights Act (1964) undermined the remaining structure of Jim Crow laws and provided federal protection in the exercise of civil rights. The Voting Rights Act (1965) provided for federal action to put an end to interference by local governments and individuals with the right of African Americans to register and vote. Both these laws were upheld in challenges before the U.S. Supreme Court.