King, Martin Luther, Jr., 1929–68, American clergyman and civil-rights leader, b. Atlanta, Ga., grad. Morehouse College (B.A., 1948), Crozer Theological Seminary (B.D., 1951), Boston Univ. (Ph.D., 1955). The son of the pastor of the Ebenezer Baptist Church in Atlanta, King became (1954) minister of the Dexter Ave. Baptist Church in Montgomery, Ala. He led the black boycott (1955–56) of segregated city bus lines and in 1956 gained a major victory and prestige as a civil-rights leader when Montgomery buses began to operate on a desegregated basis.

King organized the Southern Christian Leadership Conference (SCLC), which gave him a base to pursue further civil-rights activities, first in the South and later nationwide. His philosophy of nonviolent resistance led to his arrest on numerous occasions in the 1950s and 60s. His campaigns had mixed success, but the protest he led in Birmingham, Ala., in 1963 brought him worldwide attention. He spearheaded the Aug., 1963, March on Washington, which brought together more than 200,000 people. The protests he led helped to assure the passage of the Civil Rights Act of 1964, the year he was awarded the Nobel Peace Prize. The following year King and the SCLC led a campaign for African-American voter registration centered on Selma, Ala. A nonviolent march from Selma to Montgomery was attacked by police who beat and teargassed the protestors, but it ultimately succeeded on the third try when the National Guard and federal troops were mobilized. The events in Selma provoked national outrage, and months later aroused public opinion did much to precipitate passage of the 1965 Voting Rights Act.

Kings leadership in the civil-rights movement was challenged in the mid-1960s as others grew more militant. His interests, however, widened from civil rights to include criticism of the Vietnam War and a deeper concern over poverty. His plans for a Poor Peoples March to Washington were interrupted (1968) for a trip to Memphis, Tenn., in support of striking sanitation workers. On