It may readily be believed that so long-continued and unrelenting a persecution of so great a man and distinguished benefactor of his country, proceeded from something more than mere envy at greatness, powerful as that principle ever is in little minds. In truth, it was part of the deep-laid plan for the restoration of the Stuart line, which the declining state of the Queen's health, and the probable unpopularity of the Hanover family, now revived in greater vigour than ever. During this critical period, Marlborough, who was still on the Continent, remained perfectly firm to the Act of Settlement, and the Protestant cause. Convinced that England was threatened with a counter-revolution, he used his endeavours to secure the fidelity of the garrison of Dunkirk, and offered to embark at its head in support of the Protestant succession. He sent General Cadogan to make the necessary arrangements with General Stanhope for transporting troops to England, to support the Hanoverian succession, and offered to lend the Elector of Hanover £20,000 to aid him in his endeavour to secure the succession. So sensible was the Electoral house of the magnitude of his services, and his zeal in their behalf, that the Electress Sophia entrusted him with a blank warrant, appointing him commander-in-chief of her troops and garrisons, on her accession to the crown.[34] [34] Coxe, vi. 263. On the death of Queen Anne, on August 1, 1714, Marlborough returned to England, and was soon after appointed captain-general and master-general of the ordnance. Bolingbroke and Oxford were shortly after impeached, and the former then threw off the mask, by flying to France, where he openly entered into the service of the Pretender at St Germains. Marlborough's great popularity with the army was soon after the means of enabling him to appease a mutiny in the guards, which at first threatened to be alarming. During the rebellion in 1715, he directed, in a great degree, the operations against the rebels, though he did not actually take the field; and to his exertions, its rapid suppression was in a great measure to be ascribed.