Commandant Captain Nathan Heald ordered that all whiskey and gunpowder be destroyed so it wouldn't be taken by the local Indian tribes allied with the British, and then abandoned the fort. A procession of 148 soldiers, women and children then left Fort Dearborn to retreat to Fort Wayne, Indiana. About two miles south of Fort Dearborn, a band of Potawatomi Indians, led by Chief Blackbird, ambushed the garrison, killing 86 of the fleeing Americans and capturing the remainder to sell as slaves to the British as prisoners.
Fort Dearborn was burned to the ground and the region remained devoid of US citizens until after the war was over.