All this came to an end when the country was settled from coast to coast. What would Americans do without the frontier? Turner wondered. We didn't. We kept right on, preserving the frontier by extending the meaning of the word. We invented "new frontiers," in space or science or medicine or politics, the most famous being the new frontier adopted as a theme of John Kennedy's presidential campaign in 1960: "We stand today on the edge of a new frontier,...a frontier of unknown opportunities and paths, a frontier of unfulfilled hopes and threats.... The new frontier...is not a set of promises, it is a set of challenges. It sums up not what I intend to offer the American people, but what I intend to ask of them."

That part of a country which lies on the limit of the settled area. It differs from a boundary because the term frontier indicates outward expansion into an area previously unsettled by a particular state. Some frontiers have occurred where two nations advance from different directions, leading to boundary disputes. A settlement frontier marks the furthest advance of settlement within a state while the political frontier is where the limit of the state coincides with the limit of settlement.

Modern dance in one act, with choreography by Graham, music by Horst, set by Noguchi, and costumes by Graham. Premiered 28 Apr. 1935 at the Guild Theater, New York, with Graham and her company. It portrays the determination and energy of the early pioneers. It was originally danced as part of a larger work, Perspectives Nos. 1 and 2, but the group section in this work, ‘Marching Song’, was subsequently dropped.

Commonly regarded as the area where the settled portions of civilization meet the untamed wilderness, the frontier has persisted in American history as a topic of profound importance and intense debate. The conceptualization of the frontier has shifted greatly over time, evolving from older concepts that treated the frontier as a line of demarcation separating civilization from savagery to more modern considerations that treat the frontier as a zone of interaction and exchange between differing cultures. While numerous conceptualizations of the frontier contend for acceptance by the American public, all agree that the frontier occupies an influential position in the story of the American past.

Although the frontier has fascinated Americans since the colonial era, it first came to prominence as a true ideological concept late in the nineteenth century. On 12 July 1893, a young University of Wisconsin history professor named Frederick Jackson Turner, who sought to discover an antidote to the "germ theory" of history, which argued that all American institutions evolved from European precedents transplanted into the New World by the colonists, argued that the frontier was more important than any other single factor in shaping American history and culture. An influential address delivered before the American Historical Association, Turner's "The Significance of the Frontier in American History" suggests that the process of westward migration across the North American continent unleashed forces directly responsible for shaping the national character, an argument that boldly proclaimed the exceptionalism of the American experience and downplayed Europe's influence upon the development of the United States.

For Turner, the frontier was not so much a place as a reoccurring process of adaptation and change. The lure of abundant and inexpensive land brought Anglo-Europeans westward in an effort to improve their social and economic standings. As these migrants conquered the wilderness and spread across the North American continent, they experienced challenges and hardships unlike anything previously encountered in the Western world. In Turner's estimation, the process of overcoming the frontier transformed the Anglo-Europeans into a new national form, Americans. The core traits held dear by Americans, including democracy, individualism, freedom, and thrift, were generated by their experience of taming the wilderness. Turner attributed the greatest successes of American development, from the adoption of democratic self-rule to the belief in economic egalitarianism, to the indomitable national spirit created by the westering experience of the frontier populace, average people who reshaped European values and institutions in their own image. Nonetheless, Turner conceived of the frontier as a part of the past, and, based on the assertion of the 1890 census that Americans had completely filled the territorial borders of the forty-eight contiguous states, he warned that the nation was entering into a new phase in which it could no longer count upon the abundance of western land to provide the lifeblood of American culture.

The Turner thesis, as his concept of the frontier came to be known, proved extremely influential during the first half of the twentieth century. His initial essay sparked a series of test theories, conducted both by Turner and by his students, that emphasized the uniqueness of American history and the exceptionalness of the United States among the world's great nations. One Turnerian advocate, the historian Walter Prescott Webb, even expanded Turner's frontier process to include the entire Anglo-European world. The frontier experience, according to Webb, not only redefined America but also reached across the ocean to influence the modern development of Europe, giving rise to the dominant social and political institutions of the West. In a direct reversal of the European germ theory, Webb argued that democratic government, capitalist economic theory, and individualistic Protestant religion all were directly linked to the experience of westward movement and the conquering of the American frontier.

Turner's grand scheme spawned a long line of criticism, ranging from petty oversimplifications of his arguments to sophisticated criticisms of his approach to the frontier. While the Turner thesis remains a formidable force in the study of the American frontier, his frontier process has some serious problems. Among the most noticeable is the racially exclusive environment created by the Turner thesis. Turner's frontier process is the triumphant story of the Anglo-American conquest of the wilderness, and it makes little mention of the diversity of peoples who played important roles in the history of the American frontier. For the most part, American Indians, African Americans, and Mexican and Asian immigrants do not merit consideration as influential players on the Turnerian frontier. Only the American Indians are afforded a place in Turner's world, and they are only an obstacle easily overcome in the advancement of the American nation. In addition, Turner's frontier does not attribute a significant role to women. His thesis gives no voice to the thousands of pioneering women who toiled alongside their husbands and fathers in the conquest of the American frontier, nor does he attempt to assess the contributions made by frontier women to the development of cherished American institutions. Finally, Turner's model allows no room for the diversity of the frontier experience in North America. His process of conquest and transformation does not lend itself favorably to the frontier history of New France, where cultural mediation and compromise prevailed, or to the Spanish frontier in America, which illustrates the construction of a frontier that existed more as a defensive perimeter for the core culture of Mexico than as a successive process of territorial conquest and acculturation.

During the 1980s, the problems inherent in the Turner thesis led to the codification of the critique under the leadership of a group of influential frontier thinkers known as the new western historians. Their concepts emphasized the frontier as a geographical region rather than as a process of westward movement, offering a more inclusive story of the American frontier than that allowed by Turner or his adherents. Focusing their attention primarily on the trans-Mississippi West, the new western historians argued that the historical diversity of the frontier must not be overlooked. All the peoples of the frontier, including American Indians, African Americans, Mexicans, Asians, and women, participated in shaping frontier America. In the estimation of the new western historians, the interaction of ethnic minorities with Anglo-American ideals, which in many instances was antagonistic, set many of the parameters for the subjugation of the frontier. New western historians also took issue with the celebratory climate invoked by Turner's seeming irresistible process of frontier transformation. Rather, they argued that taming the American wilderness was a fierce struggle, most appropriately designated by what one new western historian dubbed "the legacy of conquest." At the core of the reassessment is an understanding that all of the questions that dominate mainstream historical inquiry, including notions of conflict, race, gender, and society, provide fertile ground for studying the frontier. In addition, it is not a study bound by defined temporal limits but a legacy still at work. New western historians argue that the conquest of the frontier did not come to end in 1890, as Turner suggested, but that it continues during the modern era in the form of continuing legal and political battles over the finite resources of the American West.

While the new western historians posed serious challenges to the Turnerian model and questioned the perspective from which the frontier should be viewed, the debate over the significance of the frontier in American history continued unabated into the twenty-first century. Turner's frontier process was perhaps deeply flawed, but it seems undeniable that the frontier played an influential role in the development of the American nation. Perhaps for this reason twenty-first-century conceptualizations of the frontier represent a delicate melding of Turner and new western history. Modern interpretations often define the frontier as a meeting place, or contact point, where differing cultures interacted on a relatively equal footing with no one group able to assert total superiority over the other. This approach to the frontier leaves no room for Turner's unstoppable process of American advancement, but what remains is Turner's suggestion that the frontier was a unique place of contact and exchange where no culture, Anglo-American or otherwise, could remain unchanged.