The confederacy, which had its roots in pan-tribal movements dating to the 1740s, formed in an attempt to resist the expansion of the United States and the encroachment of American settlers into the Northwest Territory after Great Britain ceded the region to the U.S. in the 1783 Treaty of Paris.

The French and Indian War proved to be the largest and final Anglo-French contest for control in North America, ending with a British victory.

[6] The Shawnee responded by demanding money from settlers,[7] and formed alliances with other tribes that inhabited the region to prevent subsequent territorial losses.

[8] Early formal ties leading to the formation of the Northwestern Confederacy were made in 1774, in response to the Yellow Creek massacre and Lord Dunmore's War.

[9] Commissioners from the Continental Congress met with representatives from the Iroquois, Shawnee, Lenape, Wyandot, and Odawa in 1775 at Fort Pitt, urging them to remain neutral in the growing conflict with Great Britain.

The British Army abandoned control over several forts along the American frontier and redeployed those forces to the east, which removed an impediment to illegal settlement.

[13] Although many native peoples fought for the British in the American Revolutionary War, Great Britain made no mention of their allies in the 1783 Treaty of Paris.

"[14] Brant worked to establish a pan-Indian confederacy which could negotiate with the new United States, and delegates from 35 "nations" gathered on the upper Sandusky River in September 1783.

The Indian Affairs Committee of Congress passed the Resolution of October 15, 1783, however, which claimed the land and called on the native nations to withdraw beyond the Great Miami and Mad rivers.

The US commissioners negotiated the Treaty of Fort McIntosh in January 1785, however, in which a few Native American representatives agreed to grant to the United States most of present-day Ohio.

[20] Nevertheless, a group of Shawnee, Lenape, and Wyandot agreed to allow U.S. settlement on a tract of land north of the Ohio River in the January 1786 Treaty of Fort Finney.

[23] The Treaty of Fort Finney was rejected by a September 1786 council of 35 native nations (including British representatives) who met at a Wyandot (Huron) village on the upper Sandusky River.

[24] Logan's raid into Shawnee territory occurred weeks later, hardening native views of the U.S. That December, Brant returned from Europe to address a council on the Detroit River.

He did not arrive until summer 1788, when he invited the nations to a council at Fort Harmar to negotiate terms by which the United States could purchase lands and avoid war.

[28] The sight of Fort Harmar and nearby Marietta, both north of the Ohio River boundary, convinced some that the United States was negotiating from a position of strength.

The signatories of the 1786 Detroit letter to Congress were the Iroquois (the "Six Nations"), Cherokee, Huron, Shawnee, Delaware, Odawa, Potawatomi, Twitchee, and the Wabash Confederacy.

A U.S. delegation led by Rufus Putnam and John Hamtramck, with assistance from Little Turtle's son-in-law William Wells, negotiated a treaty with the tribes of the Wabash Confederacy later that year.

For a week in October, pro-war factions (especially Simon Girty, the Shawnee, and the Miami) debated moderate factions—particularly the Iroquois, represented by Cornplanter and Red Jacket.

The Shawnee and Delaware insisted that the U.S. recognize the 1768 Fort Stanwix treaty between the Six Nations and Great Britain, which set the Ohio River as a boundary.

[52] A large, combined confederacy force attacked Fort Recovery, inflicting heavy casualties and disrupting the legion's supply lines; however, it also exposed lingering inter-tribal conflicts and strategic differences.

Utilizing St. Clair's defeat and Fort Recovery as a reference point,[55] the treaty forced the northwest Native American tribes to cede southern and eastern Ohio and tracts of land around forts and settlements in Illinois Country; to recognize the United States as the ruling power in the Old Northwest, and to surrender ten chiefs as hostages until all American prisoners were returned.