Image description: This picture was taken at the Civil Rights March on Washington, D.C. on August 28, 1963. It shows Dr. Martin Luther King Jr., president of the Southern Christian Leadership Conference, and Mathew Ahmann, Executive Director of the National Catholic Conference for Interrracial Justice, in the crowd.

The march was one of the largest political rallies for human rights in U.S. history, and it was where Dr. King delivered his famous “I Have a Dream” speech.

Photo from the National Archives.