Before the 1781 Articles of Confederation could be approved, eight states that claimed the western territories had to settle the predicament. For instance, it wasn’t until 1791 that Vermont became a state previously claimed by New Hampshire and New York. Areas north of the Ohio River were claimed by Virginia, Connecticut, New York, and Massachusetts. It was only in 1786 that all the states, except for Connecticut, withdrew their claims over the territories. In 1800, Connecticut ceded the areas, including the Western Reserve. Deeper explorations of the west part of the continent began in 1804. As such, much of the discovery and expansion into the lands were government-sponsored and military expeditions.
While certain explorers such as Major Stephen Long considered the Plains “arid and forbidding,” fur trappers prospered in the region and became familiar with the territory. Much of the methods used to expand into the west consisted of political settlements between the states, land sales, and exploratory voyages that were supported by the government. Additionally, much of the expansion was supported by an ideological and religious belief, Manifest Destiny, that proposed that the American people were meant to move westwards through the continent.
The continued expansion inland was attributed to an array of issues, which led to treaties and deals. Before 1820, the Ohio River divided the free states of the Northwest from the slaveholding Southwest states. The Compromise of Missouri attempted to balance the presence of each side by allowing Missouri entrance into the Union, balanced by free-state Maine, and prohibiting slave trading in the north of Louisiana. The compromise was held until 1846, after which the slavery debate and conflict became more prominent during the Mexican-American War once again.