How did Southwest territory become part of US?

Answer 1

The Southwest Territory was established after the United States acquired the land from Great Britain following the American Revolutionary War through the Treaty of Paris in 1783. The area was further expanded by the Louisiana Purchase in 1803, which added vast territories west of the Mississippi River. Subsequently, through treaties and conflicts with Native American tribes and Mexico, the U.S. solidified its claim over the region, leading to its incorporation into the United States as states like Texas, Arizona, New Mexico, and others. The process involved both negotiation and military action, reflecting the country's westward expansion philosophy.