The existence of an area of free land, its continuous recession, and the advance of American settlement, explain American development.

The disunity of the concept of the West the similarity of American expansion to European colonialism and imperialism in the 19th century and the realities of minority group oppression revealed the limits of Turnerian and exceptionalist paradigms. His model of sectionalism as a composite of social forces such as ethnicity and land ownership gave historians the tools to use social history as the foundation of all social economic and political developments in American history. He was elected a Fellow of the American Academy of Arts and Sciences in 1911.

For other people of this same name see Frederick Jackson (disambiguation) and Frederick Turner (disambiguation)

Frederick Jackson Turner (November 14 1861 – March 14 1932) was an American historian in the early 20th century based at the University of Wisconsin until 1910 and then at Harvard. In recent years western history has seen pitched arguments over his Frontier Thesis with the only point of agreement being his enormous impact on historical scholarship and the American mind. He is best known for his essay "The Significance of the Frontier in American History" whose ideas formed the Frontier Thesis.