Mohammed IV, a Turkish sultan, born in 1042, died about the close of 1692. In 1048 he succceded his father Ibrahim L, who had been deposed and strangled by the janizaries. Mohammed Kuprili or Kuperli, an Albanian, was made grand vizier. To him, and to his son who sweceeded him, the reign of Mohammed IV. owes all it. celebrity. The sultan had neither talent nor energy, and cared little for anything but hunting, in which he spent most of his time, and lavished vast sums. The empire at his accession was in the utmost confusion, but Kuprili restored order by promptly putting to death the leaders of sedition. Ibrahim, at war with Venice, had conquered the greater part of Candia in 1645, and the war continued after Mohammed's accession. The Venetians defeated the Turkish fleet in the Archipelago in July, 1651, and destroyed a second fleet, July 6, 1656, and shortly afterward captured the islands of Lemnos and Tenedos, which the Turks regained in the following year. The contest continued with various fortune till 1667, when Ahmed Kuprili, one of the greatest of Turkish generals, who had succeeded his father as grand vizier in 1661, undertook the siege of the city of Candia, which he prosecuted with vigor for two years and four months, when the Venetian commander Moro-sini was compelled to capitulate, Sept. 16, 1669, while at the same time peace was concluded between Venice and Turkey. In 1660 war had broken out with Austria, and for some time the Turks had been highly successful in Hungary. Germany, France, and Italy combined to check their progress, and Montecuculi, general of the allies, gained a brilliant and decisive victory over them, Aug. 1, 1664, at St. Gothard on the Raab, which, followed by the treaty of Tcmesvar, put an end to the war.

In 1672 the sultan invaded Poland in person, and took Kamenetz; but John Sobieski, then grand marshal of the kingdom, in 1673 gave the Turks a total defeat at Khotin, and in 1676 obtained an honorable peace. An insurrection of the Hungarians under Tokolyi tempted the sultan in 1682 to make war again upon the emperor; and in July, 1683, an army of 300,000, commanded by Kara Mustapha, invested Vienna. The emperor fled with his family to Linz. The city was in the last extremity when Sobieski and Charles of Lorraine came to its relief, and on Sept. 12 totally routed the Turks, who suffered immense losses. After this the Turks met with nothing but disaster. Germany, Poland, Russia, and Venice combined against them; and on Aug. 12, 1687, Charles of Lorraine gave them a terrible defeat at Mohacs, which was followed by the loss of Transylvania .and other provinces. The Turkish army at length mutinied at Belgrade, marched to Constantinople in the latter part of 1687, dethroned the sultan, and raised his brother Solyman III. to the throne.

Mohammed was kept in prison till his death.