Marionville is a city in Lawrence County, Missouri, United States. The population was 2,225 at the 2010 census. Marionville is known for its large population of white squirrels. Marionville was platted in 1854. The city name has been erroneously attributed as namesake of Francis Marion. It is, in fact, named to honor early settler and founder, James Marion Moore. Other names were considered - Jamestown/Jamesville and Moorestown/Mooresville - but were already taken and Moore's middle name was then used. A post office called Marionville has been in operation since 1864. On March 12, 2006, a tornado hit the town, destroying houses and killing two people. It was rated as an F3.