The accession of Portugal in the course of this year to the Grand Alliance was important in that it opened the estuary of the Tagus as a naval base, and enabled the Archduke Charles to land with a body of troops escorted by an Anglo-Dutch fleet under Rooke and Callenberg.  This fleet later in the year (August 4) was fortunate in capturing Gibraltar without much loss, the defences having been neglected and inadequately garrisoned.  In this feat of arms, which gave to the English the possession of the rock fortress that commands the entrance into the Mediterranean, the Dutch under Callenberg had a worthy share, as also in the great sea-fight off Malaga on August 24, against the French fleet under the Count of Toulouse.  The French had slightly superior numbers, and the allies, who had not replenished their stores after the siege of Gibraltar, were short of ammunition.  Though a drawn battle, so far as actual losses were concerned, it was decisive in its results.  The French fleet withdrew to the shelter of Toulon harbour; and the allies’ supremacy in the midland sea was never again throughout the war seriously challenged.  The Dutch ships at the battle of Malaga were twelve in number and fought gallantly, but it was the last action of any importance in which the navy of Holland took part.  There had been dissensions between the English and Dutch commanders, and from this time forward the admiralties made no effort to maintain their fleet in the state of efficiency in which it had been left by William III.  The cost of the army fell heavily upon Holland, and money was grudged for the maintenance of the navy, whose services, owing to the weakness of the enemy, were not required.

The military campaign of 1705 produced small results, the plans of Marlborough for an active offensive being thwarted by the Dutch deputies.  The duke’s complaints only resulted in one set of deputies being replaced by another set of civilians equally impracticable.  There was also another reason for a slackening of vigour.  The Emperor Leopold I died on May 5.  His successor Joseph I had no children, so that the Archduke Charles became the heir-apparent to all the possessions of the Austrian Habsburgs.  Louis XIV therefore seized the opportunity to make secret overtures of peace to some of the more influential Dutch statesmen through the Marquis D’Allegne, at that time a prisoner in the hands of the Dutch.  The French were willing to make many concessions in return for the recognition of Philip V as King of Spain.  In the autumn conversations took place between Heinsius, Buys the pensionary of Amsterdam, and others, with D’Allegne and Rouille, an accredited agent of the French government.  Matters went so far that Buys went to London on a secret mission to discuss the matter with the English minister.  The English cabinet, however, refused to recognise Philip V; and, as the Dutch demand for a strong barrier of fortresses along the southern frontier of the Netherlands was deemed inadmissible at Versailles, the negotiations came to an end.