Major Francis Armstrong is buried in a small cemetery at Swallow Rock, Fort Coffee. He was Superintendent of the early Choctaw removal and also Superintendent of the Choctaw Agency when it was established in 1832. He died 1835 at the Agency and was brought to Swallow Rock, (Fort Coffee), for burial.
Francis Armstrong was the inventor of the Derringer pistol, by the authority of Dr. Park. Dr. Park adds, "My brother William Park and Hugh L. McClung were with Francis Armstrong when he gave the pattern of the pistol to Derringer."