The term "Iron Curtain" refers to the political and ideological barrier that divided Europe during the Cold War, roughly from the end of World War II in 1945 until the early 1990s. It symbolized the separation between the Western countries, led by the United States, and the Eastern bloc, dominated by the Soviet Union. This division affected international relations, military alliances, and economic systems. The phrase was popularized by Winston Churchill in a speech in 1946, where he described the curtain as a metaphor for the growing divide in Europe. The Iron Curtain represented not only physical borders but also the suppression of freedom and democracy in Eastern Europe, where many countries fell under communist influence.