John Tuthill received his formal education where he frequented the New York Universtiy and later Harvard in economics and business administration. He taught banking and finance at the Northeastern University, Boston before joining the U.S. Foreign Service in 1940. He was assigned to London as part of the staff of the Supreme Headquarters, Allied Expeditionary Force, under the command of U.S. Army Gen. Dwight D. Eisenhower. He was appointed aide to General George C. Marshall in 1947 and as such was stationed in Bonn Germany. He was involved in the establishment of the Marshall Plan's Organization for European Economic Cooperation (OEEC). Between 1956 and 1959 he was Minister for Economic Affairs at the American Embassy in Paris and in 1959 he was transferred to the Office of European Regional Affairs in Washington where he was involved in the negotiations to set up the OECD. He became U.S. Ambassador to the OECD in Paris from 1961 to 1962. He later served as the United States Ambassador to the European Economic Community in Brussels from 1962 to 1966. He was U.S. Ambassador to Brazil, from 1966 to 1969. After retiring from the Foreign Service, Ambassador Tuthill became professor of international politics at the Bologna Center of the John Hopkins University. During the same period he was also Head of the Atlantic Institute in Paris. From 1976 to 1988, he served as president of the Salzburg Global Seminar based in Austria. His autobiography, Some Things to Some Men: Serving in the Foreign Service, appeared in 1996.