H. Stuart Hughes, a leading scholar of European intellectual history and professor emeritus of history at the University of California at San Diego, died October 21, 1999, in La Jolla after a long illness.

Hughes, a native of New York City, was best known for his trilogy of works on the European intellectual scene in the late 19th century and 20th century: Consciousness and Society (1958), The Obstructed Path (1968), and The Sea Change (1975). Hughes wrote nine other books, including Contemporary Europe: A History (1961), which went through five editions, Prisoners of Hope (1983), and an autobiography, Gentleman Rebel (1990).

In 1997 his preeminence in the field was recognized with the AHA’s Award for Scholarly Distinction, which noted that he had "a strong claim to be one of the finest intellectual historians of Europe of his generation."

After earning a PhD in history from Harvard University, Hughes taught briefly at Brown University before enlisting as a private in the U.S. Army in 1941. Within three years, he had risen to chief of the Research and Analysis Branch of the Office of Strategic Services in the Mediterranean Theatre, a post he later held in Germany. In 1946, he left active duty as a lieutenant colonel to serve as chief of the State Department’s Division of Research for Europe.

In 1948 he returned to academic life, with appointments at Harvard and Stanford. Hughes was named Gurney Professor of History and Political Science at Harvard in 1969. He left Harvard in 1975 to join the History Department at UCSD, where he was named professor emeritus upon his retirement in 1986.

In addition to the Award for Scholarly Distinction, Hughes was the recipient of many academic honors and distinguished appointments, including a Guggenheim Fellowship, two decorations from the Italian government, membership in the American Academy of Arts and Sciences, a visiting membership at the Institute for Advanced Study at Princeton University, a fellowship at the Center for Advanced Study in the Behavioral Sciences at Stanford University, and foreign membership in the Accademia Nazionale dei Lincei and the Istituto per la Storia del Risorgimento Italiano in Rome.

Hughes was also noted for his political activism. In 1962, while teaching at Harvard, Hughes ran as an independent candidate for a U.S. Senate seat in Massachusetts. From 1967 to 1970, he was chairman of SANE: A Citizens’ Organization for a Sane World, which was one of the first political organizations to call for a worldwide nuclear disarmament alliance.

Hughes is survived by his wife, Judith M. Hughes, professor of history at UCSD; three children, Sandra Hughes of Chevy Chase, Maryland, Kenneth Hughes of Arlington, Virginia, and David Hughes of Berkeley, California; and five grandchildren.