In Photos: Things That Happened 50 Years Ago

A U.S Marine with several days of beard growth sits in a helicopter on July 18, 1968, after being picked up from a landing zone near Con Thein on the southern edge of the demilitarized zone in South Vietnam. His unit had just been relieved of duty after patrolling the region around the DMZ.

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A speaker addresses a mass rally in support of democracy organized by the youth of Prague at the Old Town Square in Prague, Czechoslovakia, on May 18, 1968. During a period called the “Prague Spring,” Alexander Dubček, the newly-elected leader of the Warsaw Pact nation, enacted numerous reforms loosening state control and expanding individual rights, which both encouraged citizens and angered the Soviet Union.

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