Moulton is a city in Appanoose County, Iowa, United States. The population was 607 at the time of the 2020 census. Moulton was platt…Moulton is a city in Appanoose County, Iowa, United States. The population was 607 at the time of the 2020 census. Moulton was platted in 1867. In 1873, the Burlington and Southwestern Railway was built into the settlement.