From 1985 until the collapse of the Soviet union in 1991, Gorbachev oversaw a massive overhaul of the country's economic and political policies.
His policy of glasnost, or free speech, allowed previously unthinkable criticism of the Communist Party and the state, but it also emboldened calls for independence in the Soviet Union's constituent republics — first in the Baltic states of Latvia, Lithuania, Estonia, and then elsewhere.
As the last Soviet leader, Gorbachev forged arms reduction reals with the United States and partnerships with the West to remove the Iron Curtain that had divided Europe since World War II, which saw the reunification of East and West Germany in 1990.
