Oglethorpe established a town that would help protect the southern boundary of his new colony from the Spanish in Florida. To ensure protection, he built a fortified town called Frederica. The town, Frederica, was named after the Prince of Wales, Frederick Louis (1702-1754). It was a military outpost and used to control ship travel. The fort was built on the waterfront to protect both the river and the town from the Spanish.
The town was surrounded by walls of earth and timber and served as a defensive barrier. The structure successfully repulsed the Spanish from invasion in 1742 (Battle of Bloody Marsh and Gully Hole Creek) on St. Simons Island. The town flourished for 10 more years until its military purposes ended. There was a fire in 1758 that destroyed most of the structures in Fredrica.
The National Park Service started in 1947 a series of sponsored archaeological investigations at the site. The site became a historic area under the National Park Service on October 15, 1966. It is now free of admission and open to the public.