(Ph.D., University of Arkansas, 2006): Modern Middle East; History of Islam, British and French Imperialism; United States Diplomatic History; Medieval Middle East; Modern Britain; Modern United States
(Ph.D., University of Connecticut, 1993): Colonial American History, Puritanism, American Revolution
(Ph.D., Yale University, 2008): Ancient Greece, Rome, and Egypt; Ancient Mediterranean Religions, including Judaism and Christianity; Early Islam
(Ph.D., Ohio State University, 1971): Early Modern Europe, European Diplomacy
(Ph.D., Princeton University, 1995): Chinese and Japanese History; Military History
(Ph.D., Emory University, 1973): Institutional, Legal, and Social History of Early Modern France and the Cultural History of US Cemeteries
(Ph.D., University of Virginia, 2006): Economic History of the Modern United States; American Political Development
(Ph.D., Stony Brook University, 2001): History of Technology, Mass Media, and U.S. Foreign Relations (esp. American-East Asian Relations)
(Ph.D., University of Iowa, 1963): History of Modern Christianity from the Reformation to the Present; History of Religion and Politics in Europe, Australia and the United States
(Ph.D., Northwestern University, 1998): American Agriculture, Environmental and Native American
(Ph.D., University of Illinois at Urbana-Champaign, 2001): Germany since 1750; European Cultural & Intellectual; Modern Middle East
(Ph.D., Stony Brook University, 2002): Colonial and Modern Mexico; Peasant and Indigenous Studies; History of Public Health, Medicine and Disease, and Environmental History
(Ph.D., University of California, Berkeley, 1971): Medieval History, Church History, Hagiography
(Ph.D., University of Cincinnati, 2005): French Empire in America; Mississippi Valley History; Environmental History
(Ph.D., Rutgers University, 1972): American Military History with particular interests in the twentieth century, civil-military relations, the interplay between societal development and military institutions, American notions about the nature of war, and aspects of American military aviation; American Cultural History and, as an element of that, the History of Sport with special interest in the emergence of mass popular culture
Modern and Contemporary China, Japan, the History of Imperialism, and World History
(Ph.D., Ohio State University, 1987): Military History, U.S. Military History, Japanese History
(Ph.D., Queen's University at Kingston, 1997): Military History, 19th and 20th Century Britain, 19th and 20th Century European Diplomacy
(Ph.D., Kansas State University, 2001): 19th century United States history, specifically 19th century U.S. political and military history and the Civil War
(Ph.D., University of Colorado, 1987): Environmental, Kansas, and U.S. Western History
(Ph.D., Yale University, 1997): Russia and the Soviet Union, military history, South Asia
(Ph.D., University of Florida, 1991): United States Constitutional and Legal History, American South, 19th Century U.S., Civil War and Reconstruction
(Ph.D., University of Kansas, 1984): The Progressive Era and Twentieth Century America, particularly History of American Women, History of American Medicine, History of American Higher Education, History of Professionalization, History of Social Science