On September 21, 1832, the Black Hawk War officially came to a close with a treaty approved at Fort Armstrong, on the site of present day Rock Island, Illinois. In this treaty the remaining Sac and Fox Indians agreed to cede the lands they occupied west of the Mississippi River to the United States. Black Hawk, two of his sons, and other Sac and Fox fighters had already been taken to the fort as prisoners after their captures in the wake of the Massacre at Bad Axe. After spending the winter imprisoned at Jefferson Barracks in St. Louis, the men were taken east. There they met with President Andrew Jackson and became subjects of great curiosity in the white population. After a brief period of imprisonment at Fortress Monroe at Hampton Roads, Virginia, the Sac and Fox fighters were returned to the Iowa territory to occupy the small reservation allotted their people by the Treaty of Fort Armstrong. Black Hawk died there in 1838.