The "Iron Curtain" was the symbolic, ieological, and physical boundary dividing Europe into two separate areas from the end of World War II until the end of the Cold War, roughly 1945 to 1991. At both sides of the Iron Curtain, the states developed their own international economic and military alliances, COMECON and the Warsaw Pact on the east side with the USSR as most important member, and the NATO and the European Community on the west side, with the United States as its most important member.