Decatur County is a county located in the U.S. state of Tennessee. As of the 2020 census, the population was 11,435. Its county seat is Decaturville.

Perry County is a county located in the U.S. state of Tennessee. As of the 2020 census, the population was 8,366, with an average population density of 20.2 persons per square mile, making it the least densely populated county in Tennessee. Its county seat and largest town is Linden. The county is named after American naval commander and War of 1812 hero Oliver Hazard Perry.