Faced with a shortage of food and expiring levies, St. Clair's army of 1,486 and 200 camp followers finally departed Fort Washington in October 1791, by which time the confederation had time to prepare. St. Clair stopped to erect Fort Jefferson as a supply depot, and continued North towards Kekionga, but the army and followers had dwindled to a combined mass of 1,120 by November. At dawn on 4 November 1791, St. Clair's force was camped (near modern Fort Recovery, Ohio) with weak defenses set up on the perimeter. A Native American force of about 2,000 warriors, led by Little Turtle and Blue Jacket, struck quickly. Surprising the Americans, they soon overran the poorly prepared perimeter. The barely trained recruits panicked and were slaughtered, along with many of their officers, who frantically tried to restore order and stop the rout. After 4 hours, St. Clair ordered an evacuation, abandoning the wounded. The small Fort Jefferson could not protect the retreating forces, and they were forced to continue all the way to Fort Washington for safety. The U.S. casualty rate was 69%, based on the deaths of 632 of the 920 soldiers and officers, with 264 wounded. Nearly all of the 200 unarmed camp followers were killed, for a total of about 832 deaths—the highest United States losses in any of its battles with Native Americans. St. Clair and his aide-de-camp were among the wounded. With a casualty rate of 97%, St. Clair's Defeat remains one of the worst disasters in U.S. Army history.