Clarksville is the county seat of Montgomery County, Tennessee, United States. It is the fifth-most populous city in the state, after Nashville, Memphis, Knoxville, and Chattanooga. The city had a population of 166,722 as of the 2020 census. It is the principal central city of the Clarksville metropolitan area, which consists of Montgomery and Stewart counties in Tennessee and Christian and Trigg counties in Kentucky. The city was founded in 1785 and incorporated in 1807, and named for General George Rogers Clark, frontier fighter and Revolutionary War hero, and brother of William Clark of the Lewis and Clark Expedition. Clarksville is the home of Austin Peay State University; The Leaf-Chronicle, the oldest newspaper in Tennessee; and neighbor to the Fort Campbell, United States Army post. The site of the 101st Airborne Division (Air Assault), Fort Campbell is located about 10 miles (16 km) from downtown Clarksville and straddles the Tennessee-Kentucky state line.