Leon Edel (born September 9, 1907, Pittsburgh, Pennsylvania, U.S.—died September 5, 1997, Honolulu, Hawaii) was an American literary critic and biographer, who was the foremost 20th-century authority on the life and works of Henry James.
Edel grew up in Saskatchewan, Canada, and graduated from McGill University (B.A., 1927; M.A., 1928). He received a doctorate of letters from the University of Paris (1932). In Paris he met American author Edith Wharton, a close friend of James’s, who provided him with information that gave him a scholarly advantage over later biographers and ultimately a deeper insight into how his subject’s personality related to his art. Edel taught English for two years in Montreal, but he soon returned to Paris and pursued research on James. He served in the U.S. Army from 1943 to 1947. In 1949 he published a complete edition of James’s plays, and the following year he joined the faculty of New York University (1950–72; thereafter professor emeritus). In 1963 he won a Pulitzer Prize and a National Book Award for the second and third volumes (Henry James: The Conquest of London, 1870–1883 and Henry James: The Middle Years, 1882–1895, both published in 1962) of a definitive five-volume biography completed in 1972. He edited The Complete Tales of Henry James, 12 vol. (1963–65), and Henry James Letters, 4 vol. (1974–84). In addition to teaching at the University of Hawaii (1972–78), Edel lectured in later years.
He also completed critical biographies of Willa Cather (Willa Cather: A Critical Biography [1953, reissued 1987; written with E.K. Brown]) and Henry David Thoreau (Henry D. Thoreau [1970]) and edited the papers and diaries of critic Edmund Wilson. His reflections on his craft are published in Literary Biography, rev. ed. (1975), taken from a series of lectures (1957) at the University of Toronto, and Writing Lives: Principia Biographica (1984, reissued 1989).