How did the United States deal with the Indian threat in the Ohio River Valley region in the War of 1812?

The United States’ conflict with American Indians began well before the War of 1812. Prior to the American Revolution (1775–1783), the British government had actually attempted to keep peace with the American Indians by prohibiting white settlement in the Ohio region. Following the British loss in the American Revolution, the British continued to supply the American Indians with weapons in the hope that it would hinder the new nation’s expansion. Nonetheless, white settlers moved into Ohio Country, where there was a string of struggles between them and the American Indian residents, known as the Ohio Indian Wars.
The American Indians were reluctant to relinquish the land they had long occupied, and the US was unable to adequately handle the Indian threat in the 1780s—so, the US proposed a treaty, the Treaty of Fort Harmar (1789). This treaty would confine the American Indians to a small portion of their former territory. Thus, many of the American Indians did not uphold the terms of the treaty, which resulted in many clashes between the two, spilling both settler and American Indian blood.
For the next twenty years, a Shawnee leader called Tecumseh rose as the greatest threat to the US. Tecumseh had wanted to unite American Indian tribes to give them a better chance at beating the United States; however, this idea never fully came to fruition, as many tribes did not want to betray the trade deals they had already established with the US. The followers he was able to bolster congregated in Prophetstown. In 1811, the US military moved on Prophetstown, launching the Battle of Tippecanoe. This battle resulted in a US victory and the death of many American Indians; subsequently, the natives began a series of revenge killings.
When the War of 1812 began, many native warriors chose to fight with the British. As a result, the US closed trading posts, leaving some tribes without adequate supplies, causing even more natives to turn to the side of the British. During the War of 1812, the US. fought a successful battle at Lake Erie, after which the British quickly retreated. US General William Henry Harrison pursued the British, and they met again at Moraviantown on the Thames River. Here, the British and Tecumseh’s American Indians faced a bitter defeat. Tecumseh himself was killed. Because Tecumseh was a symbol of the American Indian resistance, his death shattered the American Indian power, effectively ending the conflict in the Ohio Valley.
Ultimately, dealing with the American Indians in the Ohio River Valley was a lengthy trial that included offering treaties and alliances, raids/attacks on native forces, closing trading posts, and so on.
As an endnote, Tecumseh’s body, along with other native warriors’ bodies, was mutilated and dismembered after the Battle of Thames, illustrating the hatred that the conflict had created—not much mercy was shown here. After the battle, treaties were again proposed to the remaining American Indians.
https://ohiohistorycentral.org/w/Ohio_Indian_Wars