Frederick Jackson Turner's The Frontier in American History dominated the historical profession for almost half a century after it was delivered in 1893. The "frontier thesis" offered a compelling interpretation of how the frontier played the decisive role in shaping a distinctly American identity. Traditionally, most historians argued that America's important institutions derived from English and European sources, and when they did look for the origins of an "American" character, they focused on eastern groups, such as the Puritans of New England. Completely rejecting the reigning orthodoxy, Turner argued that the crucial element transforming Europeans into Americans was the process of settling the continent. Today his essay remains a profound influence on how Americans imagine themselves as individuals and as a nation.