From a political point of view, the Methuen treaty assured the very existence of Portugal; in all times of danger it could now count upon the support of the great power whose interest it was to have an ally from whose country it could act against Spain. On March 7, 1704, the Archduke Charles arrived at Lisbon with a powerful English fleet under Sir George Rooke, conveying ten thousand English troops under the command of Henri de Ruvigny, Lord Galway. On April 30, Philip V. declared war against Portugal, and the English advanced with a subsidiary Portuguese army under the Count das Galveras and Diniz de Mello e Castro. The campaign was successful; the allies took Salvaterra and Valença, and Sir George Rooke surprised the important fortress of Gibraltar. In the following year but little was done on the Portuguese frontier, because the Archduke Charles had sailed round to Barcelona, and King Pedro, who felt himself to be dying, gave up all active interest in affairs, and made over the regency to his sister Catherine, Queen-dowager of England. Had he been conscious he might have heard of the great successes and reverses of the campaign of 1706. Lord Galway and Dom João de Sousa, Marquis das Minas, advanced into Spain, and after taking Alcantara, Coria, Truxillo, Placencia, Ciudad Rodrigo, and Avila in rapid succession, occupied Madrid on July 2, 1706. But they did not remain there long; the Spaniards rose in arms for Philip V., and in August, 1706, the allied army fell back as quickly as it had advanced. Dom Pedro, however, remained unconscious of these stirring events; he gradually sank, and died at Alcantara on December 9, 1706, leaving a reputation of having been one of the best of the kings of Portugal. The great interest of his reign is to be found in the gradual formation of the English alliance, which is the clue to the Portuguese history of the next century. It was commenced by the marriage of Catherine de Braganza to Charles II., strengthened by the action of Lord Sandwich and Sir Richard Southwell in making peace with Spain, and finally cemented by the Methuen treaty, and it is curious to note that the first link in this chain was forged by Louis XIV. and Mazarin in recommending the marriage of Charles II.