The establishment of the Berlin Wall in 1961 was primarily a response to the mass emigration of East Germans to the West during the post-World War II period. As East Germany struggled with economic hardships and political oppression, many sought refuge in West Berlin, leading to a significant brain drain. The East German government, with the support of the Soviet Union, built the wall on August 13, 1961, to prevent citizens from fleeing. The wall became a stark symbol of the Cold War, representing the division between East and West, and remained until its fall in 1989.