Jeffreys-Jones attended the University College of Wales at Aberystwyth (now Aberystwyth University), taking a B.A. in 1963. During 1964-65 he pursued graduate study at the University of Michigan and, during 1965-66, at Harvard University. In 1967 he took his PhD in American history at Cambridge University in England.
He taught as a tutor of history at Harvard's Kirkland House, at Fitzwilliam College, Cambridge University, and for the Transport and General Workers Union before becoming a lecturer in history at the University of Edinburgh in 1967. After rising through the academic ranks --- lecturer and reader --- by 1997 he became the University's first professor of American history. During his career, Jeffreys-Jones held various visiting appointments, including: a Postdoctoral Fellowship at the Charles Warren Center for the Study of American History at Harvard (1971-72); a Stipendiary at the JFK Institut für Nordamerikastudien, Berlin, Germany; and a Canadian Commonwealth Fellowship and Visiting Professor at the University of Toronto.
Jeffreys-Jones began his scholarly pursuits examining the issue of violence in American industry during the Progressive Era, including the use of private detective agencies in labor disputes. He then shifted his scholarly focus to examine American intelligence when he published an historical survey examining the development of American intelligence from the establishment of the Secret Service in the 19th Century to the CIA in the 20th. This was followed by histories of the CIA, American intelligence and exaggeration, and the FBI.
Professor Jeffreys-Jones has directed a large number of postgraduate students, master's and doctoral alike. His most recent doctoral students include: Thomas C Wales, "The Secret War in the South: The Covert Center in Algiers and British and American Intelligence in the Western Mediterranean, 1941-1945," (PhD, 2005); C. Roderick Bailey, "The Special Operations Executive (SOE) and British Policy towards Wartime Resistance in Albania and Kosovo, 1940-44," (PhD, 2004); Douglas M. Charles, "The FBI, Franklin Roosevelt and the Anti-interventionist Movement, 1939-1945" (PhD, 2002).
Forthcoming: “The Antiwar Activists.” Chapter in Mitchell K. Hall, ed., Vietnam War Era: People and Perspectives (Santa Barbara, CA: ABC-CLIO, 2008)
Forthcoming: “Rise, Fall and Regeneration: From CIA to EU.” Article accepted for publication in Intelligence and National Security.
Forthcoming: Short entries on “Central Intelligence Agency (CIA)”, “Drugs, War on (US)”, “Dulles, John Foster”, “End of History”, “Federal Bureau of Investigation (FBI)”, “Hoover, J. Edgar”, “Manhattan Project”, “National Aeronautic Space Agency (NASA)”, “NORAD (North American Defense Command)”, “Office of Strategic Services (OSS)” and “Roosevelt, Eleanor” in John Stevenson and Chris Cook, eds., The Cambridge Dictionary of Modern World History. “Commentary: Loch Johnson’s Oral History Interview with William Colby, and Johnson’s Introduction to that Interview,” in R. Gerald Hughes, Peter Jackson and Len Scott, eds., Exploring Intelligence Archives: Enquiries into the Secret State (New York: Routledge, 2008). Pp. 270-73.
“Central Intelligence Agency,” in Microsoft Encarta Encyclopedia (2007).
“The Historiography of the FBI,” in Loch Johnson, ed., A Handbook of Intelligence (New York: Routledge, 2006). Pp. 39-51.
“The Idea of a European FBI,” in Loch Johnson, ed., Strategic Intelligence, 5 vols., Vol. 4: Counterintelligence and Counterterrorism (New York: Praeger, 2006). Pp. 73-96.
“Europol and the FBI: Scope for Mutual Learning", Euobserver, 25 September 2006.
“Murder by Index Card: William Colby and the American Tradition of Atrocity Denial,” Diplomatic History, 28 (November 2004): 805-809.
“Wiseman, Sir George Eden (1885-1962),” in Oxford Dictionary of National Biography (2004).
“Women and Antiwar Activism,” in Robert J. McMahon, ed., Major Problems in the History of the Vietnam War, 3rd ed. (Boston: Houghton Mifflin, 2003): 460-66.
“Man of the People? JFK and the Cuban Missile Crisis,” Reviews in American History, 30 (September 2002): 486-91.
“U.S. Intelligence and the Cult of the Confidence Man,” The Chronicle of Higher Education Review, 22 March 2002: B12-B13.
“William Colby (1920-1996),” in American National Biography, Supplement 1 (New York: Oxford University Press, 2002): 117-118.
“The CIA Contrick,” History Today, 51 (December 2001): 20-22.
“The WORM [White Old Rich Men] and the Vietnam War,” Society for Historians of American Foreign Relations Newsletter, 32 (March 2001): 30-36.
“The Role of British Intelligence in the Mythologies Underpinning the OSS and Early CIA,” Intelligence and National Security, 15 (Summer 2000): 5-19.