Fort Moultrie is a series of fortifications on Sullivan's Island, South Carolina, built to protect the city of Charleston, South Carolina. The first fort, formerly named Fort Sullivan, built of palmetto logs, inspired the flag and nickname of South Carolina, as "The Palmetto State". The fort was renamed for the U.S. patriot commander in the Battle of Sullivan's Island, General William Moultrie. During British occupation, in 1780–1782, the fort was known as Fort Arbuthnot.