He was born in Dayton, Ohio, and moved with his family over much of the USA while a young child. He was brought up from age 11 in Madisonville, a neighborhood in Cincinnati, Ohio. He entered Harvard College in 1885. On graduation in 1889 he took a post teaching classics at the College of Montana. After two years, he went to study in France, at the École Pratique des Hautes-études linked to the Sorbonne. There he studied Pali literature and Buddhism, for a year. Then he took a master's degree at Harvard, including Sanskrit.
At this point he moved away from a career as a classical scholar, taking a teaching position at Williams College in romance languages — just for one year, as it turned out. He then was offered in 1894 an instructor's position, again at Harvard, in French. He was to stay at Harvard, rising from the ranks to become a full professor of French literature in 1912. He is credited with introducing the study of comparative literature there.
It was in the early 1890s that he first allied himself with Paul Elmer More in developing the core doctrines that were to constitute New Humanism. In 1895 he gave a lecture What is Humanism?, which announced his attack on Rousseau. At the time Babbitt had switched out of classics; he would later clarify his position on the contemporary textual and philological scholarship demanded in that area, in the Germanic tradition, as a finite task, which he was unhappy to see placed above teaching based on 'eternal' content. His ideas, and More's, were characteristically written as short pieces or essays,and later gathered into books. Babbitt's Literature and the American College (1908) caused a stir, but it was assembled from writings already circulated.
He continued to publish in the same vein, often derogatory of figures from the French literature that was his avowed specialism. He also singled out Francis Bacon, and denounced 'naturalism' and utilitarianism. He met with increasing controversy down the years: those provoked into announcing their opposition included R. P. Blackmur, Oscar Cargill, Ernest Hemingway, Harold Laski, Sinclair Lewis, H. L. Mencken, Joel Elias Spingarn, Allen Tate, and Edmund Wilson. In the case of Mencken, at least, Babbitt gave as good as he got; he branded Mencken's writing as "intellectual vaudeville", a criticism with which posterity has had some sympathy.
He had an early influence on T. S. Eliot, a student of his at Harvard. Eliot in his 1926 essay The Humanism of Irving Babbitt, a review of Democracy and Leadership, had become equivocal, finding Babbitt's humanism too secular; his position vis-à-vis religion is still debated.
The identifiable figures of the New Humanist movement, besides Babbitt and More, were mostly influenced by Babbitt on a personal level and included G. R. Elliott (1883-1963), Norman Foerster (1887-1972), Frank Jewett Mather (1868-1953), Robert Shafer (1889-1956) and Stuart Pratt Sherman (1881-1926). Of these, Sherman moved away early, and Foerster, a star figure, later reconsidered and veered towards the New Criticism.
More peripherally, Yvor Winters and the Great Books movement are supposed to have taken something from New Humanism. Followers at a distance include Milton Hindus, Russell Kirk, Nathan Pusey, Peter Viereck, Richard M. Weaver and George Will. Some relationship has been traced between Babbitt and Gordon Keith Chalmers, Walter Lippmann, Louis Mercier, Austin Warren; claims in cases where such influence are not acknowledged are not easy to sustain, and Babbitt was known to advise against public tributes.
From a position of high prominence in the 1920s, having the effective but questionable support of The Bookman, New Humanism experienced a rapid drop from fashionable status after Babbitt died in 1933. By the 1940s it was being pronounced nearly extinct. A revival in interest was seen in the 1980s, and Babbitt is often name-checked in discussions on cultural conservatism.
The position of Irving Babbitt Professor of Comparative Literature was endowed by Harvard University in 1960. The National Humanities Institute runs an Irving Babbitt Project.