Born: 1783-XX-XX North Carolina
Duncan was the first settler in Helvetia, Illinois, in 1804. He fought in the War of 1812 and earned appointment as Justice of the Peace in 1817, winning reelection in 1827 when the office became elected. In all, he served for almost forty years. Duncan also served as postmaster for several years. He had five children. He was one of the original incorporators of the Mississippi and Illinois Railroad Company, which ran in Warren, Knox, and Peoria counties. In 1850, he was working as a farmer and owned $4,000 in real estate.
Gravestone, Gullick Cemetery, Highland, IL; U.S. Census Office, Seventh Census of the United States (1850), Madison County, IL, 567; W. T. Norton, ed., Centennial History of Madison County, Illinois and Its People 1812 to 1912 (Chicago: Lewis, 1912), 1:175, 525; An Act to Incorporate the Mississippi and Illinois Rail-road Company.