Mikhail Gorbachev played a key role in ending the Soviet Union’s post-World War II domination of eastern Europe. Gorbachev helped take down the long-standing Iron Curtain separating Eastern communist states and Western noncommunist states. In foreign affairs, Gorbachev cultivated friendlier relations with noncommunist states, including and especially the United States. Gorbachev worked with U.S. President Ronald Reagan to lessen the political and military tension between the United States and the Soviet Union. In so doing, Gorbachev helped end the Cold War. In 1990 Gorbachev received the Nobel Peace Prize for his “leading role in the peace process” in Europe.