Dry Tortuga

Dry Tortuga was one of the many forts in the Caribbean during the Golden Age of Piracy. Like most of the forts in the West Indies, it was under the control of the Spanish Navy. The pirate Edward Kenway attacked the fort when he roamed the area, using the Jackdaw to destroy its defences, after which he and his crew infiltrated the fort. Edward managed to kill the high-ranking officers and the commander of the fort, after which the fort fell under his control.

Reference

 * Assassin's Creed IV: Black Flag