In what areas did the united states expand its territory in the 1830s and 1840s ? what events and factors drove this expansion?

The areas that the United States expanded territory in during the 1830s and 1840s was the northwest and southwest region, this included what is now known as California, Nevada, New Mexico, Texas, Utah, and Arizona. The expansion happened westward because people wanted a better life, they wanted new markets, an in the case of some people like Mormons, they wanted a better type of freedom. The land was cheap and everyone believed that Americans were meant to develop the area.