The Iron Curtain was the political and physical boundary that divided Europe from the end of World War II in 1945 until the end of the Cold War in 1991. East of the Iron Curtain were the smaller states controlled by the Soviet Union, in 1955 formally allied by the Warsaw Pact. Many nations to the west of this geopolitical divide were NATO members. Over time these economic and military alliances developed into broader, more entrenched, cultural barriers that deepened widespread distrust on both sides. Initially, the term "Iron Curtain" was a literal description of physical barriers such as razor wire, fences, walls, minefields, and watchtowers along the borders of the opposing powers. But the term eventually took on a broader, symbolic meaning perceived as a generalized "differentness" of ideology, economy, government, and way of life that emerged when the Cold War severed earlier cultural connections between European populations.
The term's origin is often attributed to the speech "Sinews of Peace" delivered by Winston Churchill on 5 March 1946 in Fulton, Missouri where he said: "an iron curtain has descended across the Continent. Behind that line lie all the capitals of the ancient states of Central and Eastern Europe." In fact, the phrase was originally used by Queen Elisabeth of Belgium, when in 1914 when she described an "Iron Curtain" descending between her people and the nation of Germany.