George Frost Kennan was an American diplomat and historian. He was best known as an advocate of a policy of containment of Soviet expansion during the Cold War. He lectured widely and wrote scholarly histories of the relations between the USSR and the United States. He was also one of the group of foreign policy elders known as "The Wise Men".

Containment was a geopolitical strategic foreign policy pursued by the United States during the Cold War to prevent the spread of communism after the end of World War II. The name was loosely related to the term cordon sanitaire, which was containment of the Soviet Union in the interwar period.