Martin Luther King, Jr. (Jan. 15, 1929April 4, 1968), was one of the main leaders of the American civil rights movement. A Baptist minister by training, King became a civil rights activist early in his career, leading the Montgomery Bus Boycott and helping to found the Southern Christian Leadership Conference. Martin Luther King Jr. Day is a United States holiday marking the birthdate of King and observed on the third Monday of January each year, around the time of King's birthday. It is one of four United States federal holidays to commemorate an individual person. Kings public efforts led to the 1963 March on Washington, where King delivered his I Have a Dream speech, raising public consciousness of the civil rights movement and establishing King as one of the greatest orators in American history. In 1964, King became the youngest person to receive the Nobel Peace Prize for his efforts to end segregation and racial discrimination through civil disobedience and other non-violent means. King was assassinated on April 4, 1968, in Memphis, Tennessee. He was posthumously awarded the Presidential Medal of Freedom in 1977. Martin Luther King Day was established as a national holiday in the United States in 1986. In 2004, King was posthumously awarded a Congressional Gold Medal. During the 1980s, questions were raised regarding the authorship of King's college dissertation, other papers, and speeches. Concerns about his doctoral dissertation at Boston University led to a formal inquiry by university officials, which concluded that approximately a third of it had been plagiarized, but it was decided not to revoke his degree, since the original part of the paper still makes an intelligent contribution to scholarship.