Martin Luther King Jr. was an American Baptist minister and activist who became the most visible spokesperson and leader in the civil rights movement from 1954 through 1968. King became a civil rights activist early in his career. He led the 1955 Montgomery bus boycott and helped found the Southern Christian Leadership Conference (SCLC) in 1957. He also helped to organize the 1963 March on Washington, where he delivered his famous "I Have a Dream" speech. On October 14, 1964, King received the Nobel Peace Prize for combating racial inequality through nonviolent resistance. In 1968, King was planning a national occupation of Washington, D.C., to be called the Poor People's Campaign, when he was assassinated on April 4 1968 in Memphis, Tennessee. King's death was followed by riots in many U.S. cities. King was posthumously awarded the Presidential Medal of Freedom and the Congressional Gold Medal. Martin Luther King Jr. Day was established as a holiday in numerous cities and states beginning in 1971, and as a U.S. federal holiday in 1986.