Martin Luther King Jr. was a Baptist minister and leader of the American civil rights movement in the 1950s and 1960s. He led the 1955 Montgomery Bus Boycott and helped found the Southern Christian Leadership Conference. King advocated for civil and economic rights through nonviolent civil disobedience. His most famous speech was the 1963 "I Have a Dream" speech. King's legacy includes his contributions to dismantling racial segregation and advancing equal rights through peaceful protest, as well as his national holiday in his honor.