Milton Martin Klein was born on August 15, 1917 in New York City. He earned his BS (1937) and MS (1939) at The City College in New York and his PhD (1954) at Columbia University in New York. Before coming to the University of Tennessee, Klein was a Lecturer in History at Columbia University (1954-1957), the Chair of the Department of History at Long Island University (1958-1962), the Dean of the College of Liberal Arts and Sciences at Long Island University (1962-1966), and the Dean of Graduate Studies and Research at the State University of New York College at Fredonia (1966-1969). Klein joined the University of Tennessee faculty as a Professor of History in 1969. He earned a great deal of respect in this position, and was honored as the Alumni Distinguished Service Professor (1977-1985) and as the Lindsay Young Professor of History (1980-1985). After Klein's official retirement in 1985, he served as the University Historian (1988-1997). Milton Klein died on June 10, 2004 in Knoxville, Tennessee.

Klein wrote a number of books during his career, including Social Studies for the Academically Talented Student (1960), The Politics of Diversity: Essays in the History of Colonial New York (1974), New York in the American Revolution: A Bibliography (1974), The Twilight of British Rule in Revolutionary America (with Ronald Howard, 1983), The American Whig: William Livingston of New York (1990), and Volunteer Moments: Vignettes of the History of the University of Tennessee, 1794-1994 (1994).