George Frost Kennan, an expert on the diplomatic history of Russia, the Soviet Union, and U.S.–Soviet relations, joined the Faculty of the School of Historical Studies in 1956. Kennan is perhaps best known as the author of the “Long Telegram,” dispatched in 1946 to Secretary of State James Byrnes, which proposed a new approach to U.S.-Soviet relations and defined the terms of the Cold War. While the Institute was Professor Kennan’s academic home, he moved between the diplomatic and academic worlds, serving as Ambassador to the Soviet Union in 1952 and to Yugoslavia in 1960–63.