The “Long Telegram” was sent by George Kennan from the United States Embassy in Moscow to Washington, where it was received on February 22nd 1946. The telegram was prompted by US enquiries about Soviet behaviour, especially with regards to their refusal to join the newly created World Bank and International Monetary Fund. In his text, Kennan outlined Soviet belief and practice and proposed the policy of 'containment', making the Telegram a key document in the history of the Cold War. The name 'long' derives from the telegram's 8000 word length

The single document that best illustrated American anti-communism and general suspicion of Soviet aspirations, was George Kennan’s famous Long Telegram of 1946. The Long Telegram was perhaps the most cited and most influential statement of the early years of the Cold War. George Kennan had been a American diplomat on the Soviet front, beginning his career as an observer of the aftermath of the Russian Civil War. He witnessed collectivization and the terror from close range and sent his telegram after another two years’ service in Moscow from 1944 to 1946 as chief of mission and Ambassador Averell Harriman’s consultant. In 1946, Kennan was 44 years old, fluent in the Russian language and its affairs, and decidedly anti-communist. The essence of Kennan’s telegram was published in Foreign Affairs in 1947 as The Sources of Soviet Conduct and circulated everywhere. The article was signed by “X” although everyone in the know knew that authorship was Kennan’s. For Kennan, the Cold War gave the United States its historic opportunity to assume leadership of what would eventually be described as the “free world.”