Vincennes is a city in and the county seat of Knox County, Indiana, United States. It is located on the lower Wabash River in the southwestern part of the state, nearly halfway between Evansville and Terre Haute. Founded in 1732 by French fur traders, notably François-Marie Bissot, Sieur de Vincennes, for whom the Fort was named, Vincennes is the oldest continually inhabited European settlement in Indiana and one of the oldest settlements west of the Appalachians. The population was 16,759 at the 2020 census.

Knox County is a county in the U.S. state of Indiana in the United States. The oldest county in Indiana, it was one of two original counties created in the Northwest Territory in 1790, alongside St. Clair County, Illinois. Knox County was gradually reduced in size as subsequent counties were established. It was established in its present configuration when Daviess County was partitioned off. At the 2020 United States Census, the county population was 36,282. The county seat is Vincennes.