An international organization, begun in 1949. The members have pledged to settle disputes among themselves peacefully and to defend one another against outside aggressors. The founding members of NATO are Belgium, Canada, Denmark, Britain, Iceland, Italy, Luxembourg, The Netherlands, Norway, Portugal, and the United States. Greece, Spain, Turkey, and Germany became members later. France was a founding member, but withdrew from NATO's military command in 1967. The Warsaw Pact was signed by the Soviet Union and its allies largely in response to the formation of NATO. Since the end of the cold war, the Czech Republic, Hungary, and Poland have joined.