Thomas Corwin Mendenhall II (July 10, 1910 in Madison, Wisconsin – July 18, 1998 on Martha's Vineyard, Massachusetts) was a professor of history at Yale University, the sixth President of Smith College, and the leading authority on the history of collegiate rowing in the United States.
The grandson and namesake of Thomas Corwin Mendenhall (1841-1924), physicist and meteorologist, his father was a Professor of Physics at the University of Wisconsin–Madison, Charles Elwood Mendenhall (1872-1935), and his mother, Dorothy Reed Mendenhall (1874-1964), a well-known pediatrician. The young Thomas Mendenhall grew up in Madison, Wisconsin and went to Andover before graduating from Yale University in 1932. At Yale, he served on the business staff of campus humor magazine The Yale Record. Awarded a Rhodes Scholarship, he attended Balliol College, Oxford in 1935-36, earning a B.Litt. degree. While at Oxford, he was captain of the Balliol Boats. Mendenhall returned to Yale, where he wrote his doctoral dissertation on the Welsh wool trade in the 16th and 17th centuries, receiving his Ph.D. in history in 1938. As a graduate student, he rowed on the Berkeley College (Yale) intramural crew.
He married Cornelia Isabel Baker on June 4, 1938. Together, they eventually had three daughters.
In 1937, Mendenhall was appointed an instructor in history at Yale University, promoted to assistant professor in 1942, and then to associate professor in 1946. He served additionally as assistant to the provost at Yale from 1943 to 1950; director of foreign area studies, 1944–46; director Office Teacher Training, 1958–59, and Master of Berkeley College, 1950-59. In 1951-52, he became the first occupant of the academic chair at the United States Naval War College that in 1953 would be named and carry the title of Ernest J. King Professor of Maritime History. While teaching in the Yale History Department between 1937 and 1959, he served on the University's Rowing Committee and for thirty years was a reporter on rowing events for the Yale Alumni Magazine. He also wrote numerous articles on the history of crew and collegiate rowing for The Oarsman.