The Twelfth Siege of Gibraltar was fought between September 1704 and May 1705 during the War of the Spanish Succession. It followed the capture in August 1704 of the fortified town of Gibraltar, at the southern tip of Spain, by a Anglo–Dutch naval force led by Sir George Rooke and Prince George of Hesse-Darmstadt. The members of the Grand Alliance, Holy Roman Empire, England, the Netherlands, Pro-Habsburg Spain, Portugal and the Savoy, had allied to prevent the unification of the French and Spanish thrones by supporting the claim of the Habsburg pretender Archduke Charles VI of Austria as Charles III of Spain. They were opposed by the rival claimant, the Bourbon Philip, Duke of Anjou, ruling as Philip V of Spain, and his patron and ally, Louis XIV of France. The war began in northern Europ