MAHMUD II. (1785-1839), sultan of Turkey, was the son of Abu-ul-Hamid I., and succeeded his brother, Mustafa IV., in 1808. He had shared the captivity of his ill-fated cousin, the ex-sultan, Selim III., whose efforts at reform had ended in his deposition by the janissaries. The reforming efforts of the grand vizier Bairakdar, to whom he had owed his life and his accession, broke down on the opposition of the janissaries; and Mahmud had to wait for more favourable times. Meanwhile the empire seemed in danger of breaking up. In 1812 the war with Russia was closed by the Treaty of Bucharest, which restored Moldavia and the greater part of Wallachia to the Ottoman Gov ernment. But the terms of the treaty left a number of burning questions, both internal and external, unsettled ; notably in the case of the claim of Russia to Poti and the valley of the Rion (Phasis), which was still outstanding at the time of the congress of Vienna (1814-1815) and prevented the question of a European guarantee of the integrity of Turkey from being considered.
Meanwhile, within the empire, ambitious valis were one by one attempting to carve out dominions for themselves at the expense of the central power. The ambitions of Mehemet Ali of Egypt were not yet fully revealed; but Ali (q.v.) of Jannina, who had marched to the aid of the sultan against the rebellious pasha Pasvan Oglu of Widdin, soon began to show his hand, and it needed the concentration of all the forces of the Turkish empire to effect his overthrow and death (1822). The pre occupation of the sultan with Ali gave their opportunity to the Greeks whose disaffection had long been organized in the great secret society of the Hetaeria Philike, against which Metternich had in vain warned the Ottoman Government. In 1821 occurred the abortive raid of Alexander Ypsilanti into the Danubian prin cipalities, and in May of the same year the revolt of the Greeks of the Morea began the war of Greek Independence. (See GREECE : History.) The rising in the north was easily crushed; but in the south the Ottoman power was hampered by the defec tion of the sea-faring Greeks, by whom the Turkish navy had hitherto been manned.
After three abortive campaigns Mahmud was compelled, in finitely against his will, to summon to his assistance the already too powerful pasha of Egypt, Mehemet Ali, whom he had already employed to suppress the rebellious Wahhabis in Arabia. The disciplined Egyptian army, supported by a well organized fleet, rapidly accomplished what the Turks had failed to do ; and by 1826 the Greeks were practically subdued on land, and Ibrahim was preparing to turn his attention to the islands. But for the intervention of the Powers and the battle of Navarino Mahmud's authority would have been restored in Greece. The news of Navarino betrayed Mahmud into one of those paroxysms of rage to which he was liable, and which on critical occasions were apt fatally to cloud his usual good sense. After in vain attempting to obtain an apology for "the unparalleled outrage against a friendly power" he issued on Dec. 20 a solemn hatti sheriff sum moning the faithful to a holy war. This, together with certain outstanding grievances and the pretext of enforcing the settle ment of the Greek Question approved by the Powers, gave Rus sia the excuse for declaring war against Turkey. After two hardly fought campaigns (1828, 1829) Mahmud was at length, on Sept. 14, 1829, compelled to sign the Peace of Adrianople.
From this moment until his death Mahmud was, to all intents and purposes, the "vassal of Russia," though not without occa sional desperate efforts to break his chains. (For the political events of the period between the first revolt of Mehemet Ali [Sept. 1832] and the death of Mahmud see MEHEMET ALI.) The personal attitude of the sultan, which alone concerns us here, was determined throughout by his overmastering hatred of the upstart pasha, of whom he had stooped to ask aid, and who now defied his will ; and the importance of this attitude lies in the fact that, as the result of the success of his centralizing policy, and notably of the destruction of the janissaries (q.v.), the supreme authority, hitherto limited by the practical power of the ministers of the Porte and by the turbulence of the privileged military caste, had become concentrated in his own person.