In 1808, shortly before the War of 1812, Duncan moved as a young man to Natchez, Mississippi Territory, a developing river town that was important to trading along the Mississippi River [REF].
Duncan owned the following cotton and sugar plantations: L'Argent, Camperdown, Carlisle, Duncan, Duncannon, Duncansby, Ellisle, Homochitto, Middlesex, Oakley, Rescue, Reserve, Attakapas, and Saragossa [REF].