Fort Griswold is a former American defensive fortification in Groton, Connecticut. Named after then Deputy Governor Matthew Griswold, the fort played a key role in the early stages of the American Revolutionary War. In correspondence with Fort Trumbull on the opposite side of the harbor, Griswold served to defend the port of New London, a supply center for the new Continental Army and friendly port for Connecticut-sanctioned privateers who attacked British ships. The 17-acre site is maintained as Fort Griswold Battlefield State Park by the Connecticut Department of Energy and Environmental Protection.