Frederick Jackson Turner (1861-1932) was an American historian who taught at the University of Wisconsin and later at Harvard University. Turner specialized in the history of the American frontier presenting his famous “Frontier Thesis” in the essay “The Significance of the Frontier in American History” at a meeting of the American Historical Association in 1893 when he was a young professor at the University of Wisconsin.

Turner draws on his firsthand experience living in Wisconsin in the late 1800s to inform his perspective on the formative influence of frontier settlements. His academic focus on western expansion also positioned him as an authority on the frontier’s national significance and enabled him to argue decisively for the role of the frontier experience in defining American identity and culture. The essay established Turner as one of the foremost historians of the American frontier and remains his most influential work.

John C. Calhoun (1782-1850) was a prominent American statesperson who served as vice president, secretary of state, and senator during his political career.

Turner cites a speech by Calhoun from 1817 in his essay to illustrate the rapid pace of expansion and population growth in the early 19th-century United States.