A Charles Moore photo of the May, 1963, race riots in Birmingham, Ala., when the city was one of the most racially divided in the United States. (RYERSON IMAGE CENTRE)
Martin Luther King (centre) in Birmingham, Ala., in a December, 1965, photograph by Bob Fitch. (RYERSON IMAGE CENTRE)
Aug. 21, 1968: A searing photo of the invasion by Warsaw Pact troops, under Soviet orders, of Prague, Czechoslovakia (now the Czech Republic), by Hilmar Pabel. (RYERSON IMAGE CENTRE)