Somerville is a town in Morgan County, Alabama. It is included in the Decatur Metropolitan Area, as well as the Huntsville-Decatur Combined Statistical Area. As of the 2000 census, the population of the town is 347. Somerville was the county seat of Morgan County from 1818 to 1891, when the seat was moved to Decatur. The town was named for Robert M. Summerville, an officer killed in 1814 during the Creek Indian War.