In October 1791, General Arthur St. Clair ordered the construction of a fort roughly six miles south of modern-day Greenville, Ohio. He intended to use the site as a supply depot for his campaign against the Miami nation in the Ohio Country. The fort was a rough square with the walls approximately one hundred feet in length. St. Clair's men also built blockhouses on each corner of the fort. Originally called Fort Deposit, General St. Clair preferred to call the stockade Fort Jefferson.
After the fort's completion, St. Clair's army moved against the Miami. On the morning of November 4, 1791, a confederated American Indian force under Little Turtle and Blue Jacket attacked. They easily drove the Americans from the field. The American survivors fled to Fort Jefferson for safety, but they found no food or medical supplies and quickly departed for Fort Washington. This battle became known as St. Clair's Defeat. St. Clair's force suffered 647 killed soldiers and 271 wounded men out of 1400 participants in the battle. It was one of the worst defeats of the American military at the hands of Native Americans.
For the next three years, American soldiers manned Fort Jefferson. Conditions were difficult as American Indians sought to drive the invading settlers from the area and to preserve their traditional land-holdings. The United States government hoped to use Fort Jefferson for attacks on the region's American Indian inhabitants, as well as forprotection for white settlements in the area. It was an important supply depot for Anthony Wayne and his army in 1794 as they directed offensives against American Indian peoples in the area, supposedly in retaliation for the so-called "St. Clair's Defeat".
- Edel, Wilbur. Kekionga!: The Worst Defeat in the History of the U.S Army. Westport, CT: Praeger, 1997.
- Hurt, R. Douglas. The Ohio Frontier: Crucible of the Old Northwest, 1720-1830. Bloomington, IN: Indiana University Press, 1996.
- Smith, William Henry, ed. The St. Clair Papers: The Life and Public Services of Arthur St. Clair, Soldier of the Revolutionary War; President of the Continental Congress; and Governor of the North-western Territory; With His Correspondence and Other Papers, Arranged and Annotated by William Henry Smith. Cincinnati, OH: R. Clarke & Co., 1882.
- Wilson, Frazer Ells. Arthur St. Clair, Rugged Ruler of the Old Northwest; An Epic of the American Frontier. Richmond, VA: Garrett and Massie, 1944.