John P.C. Train was born 25 May 1928 in New York City to Arthur Train, a district attorney in New York City and author of the popular “Ephraim Tutt” stories that appeared in the Saturday Evening Post in the 1930s and 1940s, and Helen Coster Gerard, daughter of JP Morgan partner Charles Henry Coster. He attended the Groton School, a college preparatory boarding school located in Groton, Massachusetts. He later attended Harvard University where he received his bachelor’s degree and master’s degree and was head of The Harvard Lampoon and the Signet Society.

In 1953, he co-founded and became the first managing editor of The Paris Review. He then set up a credit-rating agency in Greece, a consulting firm in Costa Rica, and a tire-retreading company in Guinea before serving in the Army Reserves as a Sergeant and first Lieutenant and then working in Wall Street. In 1958, he founded the New York investment firm Train, Cabot, and Associates, later Train, Smith Counsel, and currently Train, Babcock Advisors. During this period, he became principle owner of Chateau Malescasse, a Cru Bourgeois wine producer. He is also chairman of the Montrose Group, investment advisors and tax accountants, and is a director of a emerging markets mutual fund.

Train later became a trustee of FRIAM (Friuli Arts and Monuments) which funded the conservation of the art and monuments of Udine after the Friuli Earthquake, Italy, in 1976. In the mid-1970s, he became involved in the Friends of Sikkim, which worked to help the region of Sikkim become a part of India. In 1980, he helped establish the Afghanistan Relief Committee to provide medicine and food to the victims of the Soviet invasion, serving first as its treasurer and later as president. In the early 1990s, he helped establish and later became trustee of the Natural History Museum Development Trust in the United States, which helped fund improvements to the British Museum of Natural History. During this time, he also became trustee of the World Monuments Fund, which helps preserve art and architecture of international importance. He is founder-chairman of the Train Foundation, previously the Northcote Parkinson Fund, which since 2000 has annually awarded the Civil Courage Prize, a human rights award which is awarded to individuals who demonstrate "steadfast resistance to evil at great personal risk — rather than military valor." He was an original trustee of the American University of Bulgaria, opened in 1991. He is an overseer of the Whitehead School of Diplomacy and International Relations at Seton Hall University and is also a member of the Council on Foreign Relations and the International Institute of Strategic Studies (London). Train has two decorations from the Italian government for humanitarian work and is an officer of the (British) Order of St. John.

John Train is the author of 25 books covering financial and investment advising as well as humor, including Money Masters of Our Time and The Midas Touch: The Strategies That Have Made Warren Buffett "America's Preeminent Investor". John Train has written several hundred columns in the Wall Street Journal, Forbes, Harvard Magazine, London’s Financial Times, and others.

A descendent of an old New England family, he is a cousin of the late Senator Claiborne Pell, chairman of the Senate Foreign Relations Committee, and of Russell E. Train, head of the United States Environmental Protection Agency under Richard Nixon and founding trustee and former chairman of the World Wildlife Fund. He has four half siblings from his father’s previous marriage to Ethel Kissam. He married Maria Teresa Cini di Pianzano and has three daughters: Helen, who was married to the late Forbes editor Paul Klebnikov, Nina, and Lisa.