Fortunately for the house of Habsburg the time of their greatest weakness was also a time of impotence and degeneracy among their foes. From the death of Mohammed III. in 1603 to the death of Murad IV. in 1640 the Ottoman empire was the prey of revolution anarchy and crime. The Sultans, effeminate puppets of a day, were in no position to take advantage of the opportunities given to them by the Thirty Years’ War. The satisfaction of their own pleasures and the preservation of their own lives were much more in their thoughts than the extension of their power. Murad IV. during the eight years of his personal rule (1632–1640) did much by a relentless severity to crush out the spirit of faction, and reduce the turbulent Janizaries to obedience, but on his death after a drinking bout in 1640, anarchy broke out again. Ibrahim I. his successor, having been with difficulty prevented from ordering a general massacre of the Christians all over the empire, contented himself by fitting out a fleet in 1645 which undertook the conquest of Candia; but the disorganisation of the government was far too great to enable the attempt to be made with any chance of success. It only provoked reprisals on the part of the Venetians and the Knights-Hospitallers. The miserable Sultan himself was deposed and murdered in 1648, the Ottoman fleet was defeated in the Ægean in 1649, civil war raged in Asia Minor, while at Stamboul ministers rapidly succeeded one another in obedience to the caprices of the harem or the demand of the soldiery. In 1656 Mocenigo the Venetian admiral occupied the Dardanelles and threatened Constantinople itself. It seemed as if the Ottoman empire was about to fall to pieces through sheer want of governance. [Sidenote: =Mohammed Kiuprili appointed grand vizier, 1656.=]