From Emmett Till to Barack Obama

obama and civil rights martin luther king
Hulton / Getty

Washington, 1963: I Have a Dream
Drawing upon an idea first proposed in 1941, the March on Washington for Jobs and Freedom was organized by civil rights groups to draw attention to the unemployment and disenfranchisement of many American blacks. On August 28, 200,000 people gathered in front of the Lincoln Memorial to listen to performances (including one by Bob Dylan, who sang "Only a Pawn in Their Game") and speeches, the most memorable of which — known popularly as the 'I Have a Dream' speech — was delivered by Martin Luther King. After the march, King and other civil rights leaders met with President Kennedy at the White House. Feeling the pressure of 200,000 Americans, Kennedy, who had initially opposed the march, agreed to put his full weight behind securing civil rights legislation.

Get the Latest Photos from Time.com
Get TIME photos and pictures of the week delivered directly to your inbox.