The conflict between Native Americans and white settlers along the Western frontier was not the primary cause of the War of 1812, but it was a major factor in the conflict. According to the Treaty of Paris, which ended the Revolutionary War, the United States claimed all the land east of the Mississippi River. The British refused to leave the forts in the Great Lakes area, and many American settlers correctly accused the British of arming the Indians. After the Revolutionary War, many settlers travelled west looking for farmland, a move they could now legally commit to after the Proclamation Line of 1763 was voided by the end of the war.
One Shawnee chief, Tecumseh, attempted to unite the Native Americans in the Old Northwestern territory to stand together against the white settlers. The British were an original ally, but after the War of 1812 slowly ended, the British lost interest in the region and left Tecumseh to fight alone. The Indian coalition lost a key battle at the Battle of Tippecanoe, and Tecumseh would go on to be slain at the Battle of the Thames in 1813.