The Iron Curtain was a physical and symbolic structure used by the Soviet Union to isolate itself from surrounding eastern and central European nations after World War II. The Iron Curtain served as a way for the Soviet Union to isolate itself politically, militarily and ideologically from other nations in Europe. The Curtain gave the Soviet Union a protective barrier to thwart military attacks, but also served as a symbolic gesture that the Soviet Union had no desire to make any contact with other nations.
Prior to its physical construction after World War II, the Iron Curtain served primarily as a metaphor. It was used sporadically to refer to nations with closed and isolative trade and political policies, but it did not rise to prominence until the late 1940s when then-British Prime Minister Winston Churchill used the phrase in a speech to refer to the physical actions of the communist states. In addition to setting a physical boundary between the Soviet Union and surrounding countries, the Iron Curtain significantly reduced positive and beneficial communications between the Soviet Union and its neighbors, such as trade and tourism. The Iron Curtain, once constructed, remained in place until the late 1980s when Communist rule in the Soviet bloc dissipated and was replaced with a multiparty system of governance.