The Justin Winsor Prize was awarded by the American Historical Association to encourage new authors to pursue the study of history in the Western Hemisphere at a time when the study of European history predominated. The award was established in 1896 and named for Justin Winsor (1831–1897), one of the founders and presidents of the American Historical Association and the long-time Librarian of Harvard University. The award was discontinued in 1938. The American Historical Association's Justin Winsor Prize is not to be confused with the present-day Justin Winsor Prize awarded annually by the Library History Round Table of the American Library Association for the best library history essay.