Ralph David Abernathy Sr. was an American civil rights activist and Baptist minister. He was ordained in the Baptist tradition in 1948. As a leader of the civil rights movement, he was a close friend and mentor of Martin Luther King Jr. He collaborated with King and E. D. Nixon to create the Montgomery Improvement Association, which led to the Montgomery bus boycott and co-created and was an executive board member of the Southern Christian Leadership Conference (SCLC). He became president of the SCLC following the assassination of King in 1968; he led the Poor People's Campaign in Washington, D.C., as well as other marches and demonstrations for disenfranchised Americans. He also served as an advisory committee member of the Congress on Racial Equality (CORE).