Because it was. The ending of the revolution and winning of independence opened up the west which lead to a steady flow of settlers to the Mississippi valley. By 1840, there were ten new western states added to the federal union. Frontier lines ran throughout 3 states on the western side of the river the line ended up touching all parts of the valley minus Wisconsin and Minnesota. A whole new part of the world had been colonized with lasting effects on American institutions, ideals and ways of