A still more delicate negotiation was pursued on the Continent. William could not allow it to appear that his expedition implied a war of religion. He would forfeit the alliance of the Emperor, which was the very pivot of his policy. Leopold was a devout and scrupulous man, and it was uncertain how he would regard an enterprise which was to substitute a Protestant dynasty for a Catholic dynasty in England. There was only one way of ensuring his assistance. In order to have the support of the Empire it was requisite to obtain the support of the Papacy. In a religious question Leopold would follow the pope. William sent one of his generals, the Prince de Vaudemont, to Rome; and, through Count Dohna, he opened a correspondence with the Vatican. He represented that the Catholics would obtain from him the toleration which they could never be sure of under James. There would be not only a serious political advantage gained by the detachment of England from the French interest, but also a positive and measurable benefit for the Church of Rome. The pope understood and assented, and took the Habsburgs with him into the camp of the Great Deliverer. This is the touch of mystery in the Revolution of 1688. James, the champion of the Church, had alienated Rome. The pope, Innocent XI, Odescalchi, is a rare and original figure, and James said truly that no man like him had sat on the see of Rome for centuries. He began the reform of the court, which consisted in the abolition of nepotism. All through the century his predecessors had founded great princely families--Borghese, Ludovisi, Barberini, Pamphili, Chigi, Rospigliosi, Altieri. These great houses grew wealthy out of the spoils of the Church, and, as their founders died without making restitution, opponents of nepotism affirmed that they died unrepentant, and might be found in those regions of the other world where Dante delighted to exhibit the pontiffs of his time. In his zeal for a strict morality Innocent tried to rectify the teaching of the Casuists, and was involved in trouble with the Jesuits. In France he was spoken of as a Jansenist, and in England Oldmixon called him a Protestant pope. He endeavoured, as nobody had done since the Reformation, to find a remedy for the divisions of Western Christendom. The movement had not ceased since Richelieu was minister and Grotius ambassador at Paris, and it became active on both sides. Innocent sanctioned a scheme of concessions which was deemed satisfactory in the universities of Protestant Germany.