If Cromwell thus had a difficulty in tearing himself away from England, where he must leave behind him rivals and declared or secret enemies, the successes of Ormond, in Ireland, soon presented themselves, compelling him to take his course. Londonderry and Dublin remained in the possession of Parliament; further, the latter city was besieged before the end of July, when the advanced guard of the Parliamentary general landed in Ireland. On the 2d of August the governor of Dublin, Michael Jones, made a successful sortie. Notwithstanding all the efforts of Ormond, the royal army, shamefully routed, found itself compelled to raise the siege. Cromwell himself landed in the port of Dublin on the 15th of August. Scarcely had he reached Ireland when he saw that all consideration towards the moderate party and the Catholics was difficult: passions were too violent and excited. English against Irish, Protestants against Catholics, republicans against royalists, it was necessary to allow full scope to be given to hatred and vengeance in order to be assured of victory. {212} Cromwell was anxious to conquer at all costs. It was under these dark auspices that the campaign began, on the 31st of August, with the siege of Drogheda, a town considerable among all those of the province of Leinster. The garrison was numerous, composed in great part of English, and they made a vigorous resistance. It was necessary to make the assault twice, and to carry the towers one by one. "I do not think," wrote Cromwell, after the victory, "that, of the whole number of the defendants, thirty have escaped with their lives. Truly I believe that it will tend to prevent the effusion of blood for the future, which are the satisfactory grounds to such actions which otherwise cannot but work remorse and regret."