1790’s - British was supplying Native Americans (Shawnee, Wyandot, and other Native American people) with weaponry, and the U.S. Army located in NW Ohio attacked NA at the Battle of Fallen Timbers.
1795- Treaty of Greenville:U.S. received the Ohio Territory and gained settlement.
1804-Lewis and Clark expedition:The LA Purchase posed an important expansion in 1804. Lewis and Clark traveled through the Rocky Mts., reached the Oregon Territory coast on the Pacific Ocean and the expedition improved relations with the NA tribes.
1811-Battle of Tippecanoe: General Harrison destroyed the Shawnee territories, that were united by Tecumseh and Prophet, which put an end to Tecumseh’s failed attempt to form an Indian Confederacy.
1812-War of 1812:The war allowed the open way for William Henry Harrison to invade Canada and defeat the British and NA forces.
Analysis
LA Purchase - improved relations with NA + developed maps and land routes for fur trappers and future settlers
NA angered by the westward movement/expansion which leads to attempt of an Indian Confederacy to defend their land
NA + American relationship is rocky mostly involving any westward expansion