Shortly after midnight on this day in 1961, East German soldiers begin laying down barbed wire and bricks as a barrier between Soviet-controlled East Berlin and the democratic western section of the city.

After World War II, defeated Germany was divided into Soviet, American, British and French zones of occupation. The city of Berlin, though technically part of the Soviet zone, was also split, with the Soviets taking the eastern part of the city. After a massive Allied airlift in June 1948 foiled a Soviet attempt to blockade West Berlin, the eastern section was drawn even more tightly into the Soviet fold. Over the next 12 years, cut off from its western counterpart and basically reduced to a Soviet satellite, East Germany saw between 2.5 million and 3 million of its citizens head to West Germany in search of better opportunities. By 1961, some 1,000 East Germans--including many skilled laborers, professionals and intellectuals--were leaving every day.

In August, Walter Ulbricht, the Communist leader of East Germany, got the go-ahead from Soviet Premier Nikita Khrushchev to begin the sealing off of all access between East and West Berlin. Soldiers began the work over the night of August 12-13, laying more than 100 miles of barbed wire slightly inside the East Berlin border. The wire was soon replaced by a six-foot-high, 96-mile-long wall of concrete blocks, complete with guard towers, machine gun posts and searchlights. East German officers known as Volkspolizei ("Volpos") patrolled the Berlin Wall day and night.

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