At the time of the Philippine Dynasty (1580-1640), Philip II of Spain ordered the construction of a new fortification on a hill adjacent to the city, to reinforce the defence of Setúbal. Recent scholars, however, have argued that the intention of the fort was also to protect a garrison loyal to the Philippine Dynasty and provide a clear indication of the Spanish king’s power, as the people of Setúbal had shown considerable opposition to Spanish rule. It was designed by Giovan Giacomo Paleari Fratino in 1583. Work on the fortress began in 1590 and was completed in 1600. During the Portuguese Restoration War the fort was the last part of Setúbal to fall to the Portuguese. Between 1649 and 1655 a “low battery” was added to provide additional defence against ships in the port.