William Michael Johnston (born 1936), known as Will Johnston, is an American historian whose field is European intellectual history. He publishes his work under the name of William M. Johnston. Since retiring from the University of Massachusetts in 1999, he has been a professor emeritus and now lives in Australia.
Johnston was educated at Harvard College, where he graduated A. B. in 1958, and later took a Ph.D. at Harvard in 1965, supervised by Crane Brinton. He established his interest in European intellectual history with such works as The Formative Years of R. G. Collingwood (1965) and The Austrian Mind: An Intellectual and Social History, 1848-1938 (1972). Before publication this had received the Austrian History Prize for best manuscript in Austrian history. At the University of Massachusetts he was the dissertation supervisor of Roderick Stackelberg, two years his junior.
Johnston retired from his university's history department in 1999 with the title of Professor Emeritus, shortly before completing his two-volume Encyclopedia of Monasticism (2000). He later migrated to Australia.
- The Formative Years of R. G. Collingwood (Harvard University Archives, 1965)
- The Austrian Mind: an Intellectual and Social History, 1848-1938 (Berkeley: University of California Press, 1972)
- Vienna, Vienna: the Golden Age, 1815-1914 (1981)
- In Search of Italy: Foreign Writers in Northern Italy since 1800 (1987)
- Celebrations: the Cult of Anniversaries in Europe and the United States Today (1991)
- Recent Reference Books in Religion: a guide for students (1996)
- Encyclopedia of Monasticism, two volumes (Chicago and London: Fitzroy Dearborn, 2000)
- Harvard Alumni Bulletin vol. 68 (1965), p. 28
- Will Johnston at umass.edu, accessed 27 September 2013
- Roderick Stackelberg, Memory and History: Recollections of a Historian of Nazism (2011), p. 88: "I chose as my dissertation supervisor the young intellectual historian William M. Johnston, who had graduated from Harvard College two years after me and had already completed his Ph.D. under Crane Brinton."