From 1815 to 1848, the UnitedStates began the process of westward expansion.  This would lead to enormous wealth in the country, but brought with it complications.  Expansion would result in the dislocation of the Native American population, war with Mexico, and increasing friction between northern and southern states over the issue of the extension of slavery.  Leaders from both regions tried to sort out their differences peacefully, but that eventually failed.

     When the time period was complete, nearly all of the lower  forty eight states would belong to the U.S. and the idea of an America that stretched from sea to shining sea was ingrained in the minds of most of the citizens.