Rosa Parks sitting on a bus in Montgomery, Alabama, 1956. (Encyclopedia Britannica)

The boycott was organized by local ministers, including Martin Luther King, Jr. (PBS)

The Martin Luther King, Jr. Research and Education Institute

Sparked by the arrest of Rosa Parks on 1 December 1955, the Montgomery bus boycott was a 13-month mass protest that ended with the U.S. Supreme Court ruling that segregation on public buses is unconstitutional.