William Graham Sumner (October 30, 1840 – April 12, 1910) was an American academic and professor at Yale College. For many years he had a reputation as one of the most influential teachers there. He was a polymath with numerous books and essays on American history, economic history, political theory, sociology, and anthropology. He is credited with introducing the term "ethnocentrism," a term intended to express his anti-imperialism, in his book Folkways (1906).