Frederick Jackson Turner

In the decade of which we write, more than two-thirds of the present area of the United States was Indian country - a vast wilderness stretching from the Great Lakes to the Pacific Ocean. East of the Mississippi, the pioneers had taken possession of the hardwoods of the Ohio, but over the prairies between them and the Great Lakes the wild flowers and grasses grew rank and undisturbed.

In 1820 the United States had a population of about nine and one- half millions; in 1830, nearly thirteen millions. It was spread out from east to west like a page in the history of society. On the Atlantic seaboard were the centers of American civilization that had grown up in colonial days in close touch with Europe. From this region of commerce and manufacture, the nation, on its march towards the west, changed through successive types of industrial life until in the Rocky Mountains the frontier fur-trader mingled with the Indians.

In the dark period of the commercial crisis of 1819, while Congress was considering the admission of Missouri, the slavery issue flamed out, and revealed with startling distinctness the political significance of the institution, fateful and ominous for the nation, transcending in importance the temporary financial and industrial ills.