Detailed map of the siege of Gibraltar (the under the command of the Earl of Portmore, with smaller maps ofthe harbor and City of Porto Bello and a the Bay and City of Havana.
The Siege of Gibraltar of 1727 (13th siege of Gibraltar and 2nd by Spain) saw Spanish forces besiege the British garrison of Gibraltar as part of the Anglo-Spanish War. After a five-month siege with several unsuccessful and costly attempts, Spanish troops gave up and retired. Following the failure the war drew to a close, opening the way for the 1728 Treaty of El Pardo and the Treaty of Seville signed in 1729.
Britain had tried to use its naval power early in the dispute, by blockading Porto Bello in Panama but the attempt proved a disaster, in which 4,000 men were lost to disease. The main objective of the blockade had been to prevent Spanish galleons leaving and sailing for Spain, but the blockaders failed in th their objective.