Clarke was educated at Yale University, Columbia University and the School of Oriental and African Studies.

Clarke is the author of 11 books, the most recent of which is The Last Campaign: Robert F. Kennedy and 82 Days That Inspired America (2008).

Clarke is a frequent speaker on topics such as writing, modern history and travel. He lives with his wife and three daughters in the Adirondacks, in upstate New York.

Nonfiction

• Dirty Money: Swiss Banks, the Mafia, Money Laundering, and White Collar Crime (1975) (with John J. Tigue)
• The Last Caravan (1978)
• By Blood and Fire: The Attack on the King David Hotel (1981)
• Lost Hero: The Mystery of Raoul Wallenberg (1982) (with Frederick E. Werbell)
• Equator: A Journey (1988)
• Pearl Harbor Ghosts (1991)
• California Fault: Searching for the Spirit of a State Along the San Andreas (1996)
• Searching for Crusoe: A Journey Among the Last Real Islands (2001) (reprinted as Islomania)
• Ask Not: The Inauguration of John F. Kennedy and the Speech That Changed America (2004)
• The Last Campaign: Robert F. Kennedy and 82 Days That Inspired America (2008)

Fiction

• Thirteen O'Clock (1984)