Robert M. Isherwood was born on April 18, 1935 in Waynesburg, Pennsylvania. He matriculated at Allegheny College in Meadville, earning his B.A. there in 1957. Isherwood then attended the University of Chicago, receiving his M.A. in 1959 and his Ph.D. in 1964. While in Chicago, he married. Isherwood has two children.

After earning his doctorate in 1964, Isherwood taught at the University of New Hampshire for three years. He then moved to Vanderbilt University's history department where he spent the remainder of his public life. He was a member of the American Historical Association, the Society for French Historical Studies, and the Soci??t?? Fran??ais d'??tude XVIII Si?ícle (the French Society for the Study of the 18th Century).

At Vanderbilt, Isherwood specialized in the French Enlightenment and paid special heed to the popular culture of the time period. His first book was Music in Service of the King: France in the Seventeenth Century (1973). It discusses the political uses that works such as Lully's tragedies lyriques could serve at the court of Louis XIV. His second book was 1986's Farce and Fantasy: Popular Entertainment in Eighteenth-Century Paris. It assesses the urban festivals of Paris during the eighteenth century. New York Times' reviewer Alan J. Plattus praised the copious detail that Isherwood assembled, detail that "challenges the convention picture of an increasing separation of popular and elite culture during the course of the 18th century." Plattus also lauds Isherwood's use of theoretical constructs to "thicken the discussion" without sacrificing clarity. In 1991, Isherwood received a Camargo Foundation fellowship to work on a book project called The Critics of Culture: The Philosophes and Musical Controversy in Eighteenth-Century France. Unfortunately, Isherwood was unable to finish the project.

Isherwood retired from Vanderbilt University in 1996 after an accident that fall forced him to take permanent disability leave. He had been working on a book entitled The Musical Enlightenment at the time of his injury. He was granted the title Professor of History Emeritus at a 2001 ceremony for having attained a ?considerable reputation among scholars of French history and the Enlightenment.