Marlborough arrived at the Hague on the 4th March; and, although no longer possessing the confidence of government, or intrusted with any control over diplomatic measures, he immediately set himself with the utmost vigour to prepare for military operations. Great efforts had been made by both parties, during the winter, for the resumption of hostilities, on even a more extended scale than in any preceding campaign. Marlborough found the army in the Low Countries extremely efficient and powerful; diversions were promised on the side both of Spain and Piedmont; and a treaty had been concluded with the Spanish malcontents, in consequence of which a large part of the Imperial forces were rendered disposable, which Prince Eugene was preparing to lead into the Low Countries. But, in the midst of these flattering prospects, an event occurred which suddenly deranged then all, postponed for above a month the opening of the campaign, and, in its final result, changed the fate of Europe. This was the death of the Emperor Joseph, of the smallpox, which happened at Vienna on the 16th April--an event which was immediately followed by Charles, King of Spain, declaring himself a candidate for the Imperial throne. As his pretensions required to be supported by a powerful demonstration of troops, the march of a large part of Eugene's men to the Netherlands was immediately stopped, and that prince himself was hastily recalled from Mentz, to take the command of the empire at Ratisbon, as marshal. Charles was soon after elected Emperor. Thus Marlborough was left to commence the campaign alone, which was the more to be regretted, as the preparations of Louis, during the winter, for the defence of his dominions had been made on the most extensive scale, and Marshal Villars' lines had come to be regarded as the _ne plus ultra_ of field fortification. Yet were Marlborough's forces most formidable; for, when reviewed at Orchies on the 30th April, between Lille and Douay, they were found, including Eugene's troops which had come up, to amount to one hundred and eighty-four battalions, and three hundred and sixty-four squadrons, mustering above one hundred thousand combatants.[28] But forty-one battalions and forty squadrons were in garrison, which reduced the effective force in the field to eighty thousand men.