Wells was adopted by a chief named Gaviahate ("Porcupine") and raised in the village of Kenapakomoko (Snakefish Town) on the Eel River, six miles north of present-day Logansport, Indiana.

While his first wife was held captive in Cincinnati, Wells married Little Turtle's daughter Wanagapeth ("Sweet Breeze"), with whom he had four children.

On 11 September 1793, Wells arrived at Fort Jefferson with news of the Grand Council's failure, blaming Alexander McKee and Simon Girty for the outcome.

[4] Wells became the equivalent of a captain in the Legion of the United States, acting as an interpreter and the head of an elite group of spies.

"[5] Wells led the First Sub-Legion to the battleground of St. Clair's Defeat (which he had fought in) and located several abandoned U.S. cannons that the Native Americans had buried.

Afterward, he led a scouting mission that discovered British officers who had brought cannonballs and powder, not knowing that the United States had already recovered the buried cannons.

[7] Wells was wounded a few days before the Battle of Fallen Timbers when, on a dare, he led his group of spies into a camp of 15 Delaware warriors and struck up a casual conversation.

The following year, he was an interpreter for the Wabash group (Miami, Eel River, Wea, Piankeshaw, Kickapoo, and Kaskaskia) at the Treaty of Greenville, in which the Native American confederation ceded most of Ohio.

Little Turtle, the last to sign the treaty, requested that Wells be sent as an Indian agent to the Miami stronghold of Kekionga, now under American control and renamed Fort Wayne.

The U.S. built an agent's house in the newly renamed Fort Wayne, and William and Sweet Breeze, with their children, moved from Kentucky to resettle with the Miami.

Washington presented Little Turtle with a ceremonial sword, and Wells was given a monthly pension of $20 ($359.00 in 2023), in compensation for his wounds at Fallen Timbers.

[10] When Thomas Jefferson became the United States' third president, Wells requested that he establish a trading post at Fort Wayne to encourage friendly relations with the area natives.

However, Wells' good standing with Harrison soon soured when he sided with Little Turtle in opposition to the 1804 Treaty of Vincennes, which gave large amounts of land to the Americans for settlement.

[15] After the marriage, Wells, his four children, and Geiger returned to Fort Wayne, where he received a discharge from the new U.S. Indian agent John Johnston.

That Autumn, the Treaty of Fort Wayne, a land deal, was signed, which led to a more militant stance on the part of Shawnee Chief Tecumseh and his brother.

Wells warned the government about this new and dangerous development, but he was largely ignored in Washington, ultimately earning the hatred of Tecumseh and his followers.

[16] William Wells continued to act as the United States Indian Agent in Fort Wayne and was able to keep the Miami out of Tecumseh's confederacy.

Wells intended to offer protection to the garrison and their families – about 96 people, about a third of whom were women and children – as they abandoned the post and walked east to Fort Wayne.