North Atlantic Treaty Organization

North Atlantic Treaty Organization (NATO), military defense organization of nations established in 1949 by Belgium, Canada, Denmark, France, Great Britain, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, and the United States. Greece and Turkey joined in 1951, West Germany in 1955 and Spain in 1982. Its purpose originally was to protect Western Europe against attack particularly by the Soviet Union and its East European satellites. The falling of the totalitarian regimes in many Eastern European countries and the Soviet policy of glasnost has greatly reduced the military threat to NATO.