The Berlin Crisis was a major confrontation of the Cold War in which the U.S.S.R. issued an ultimatum demanding the withdrawal of Western armed forces from West Berlin—culminating with the city’s de facto partition with the East German erection of the Berlin Wall, a physical barrier erected by the East German government which completely encircled West Berlin. It came to symbolize the Iron Curtain between Western Europe and the Eastern Bloc in the Cold War.
“Freedom has many difficulties and democracy is not perfect, but we have never had to put a wall up to keep our people in, to prevent them from leaving us.” —President John F. Kennedy, June 26, 1963