Russia, who, by the convention of Akkerman in October, 1826, had compelled Turkey to recognise the autonomy of Serbia and Moldo-Wallachia and cede her the ports of the coast of Circassia and Abkasia, declared war on her again on April 26, 1828, after the manifesto she had issued to her Moslem subjects on December 28, 1827. The Russians took Braila, advanced as far as Shumla, captured Varna, and laid siege to Silistria, but the plague and food shortage compelled them to make a disastrous retreat. In Asia they took Kars, Akhalzikel, and Bayazid. The next year they entered Erzerum; Diebitch captured Silistria, outflanked the Grand Vizier’s army shut up in Shumla, crossed the Balkan mountains, and laid siege to Adrianople. On September 14, 1820, Turkey signed a treaty in the latter town, which put Moldavia, Wallachia, and Serbia under Russian protectorate, and by which she ceded to Russia all the coast of Transcaucasia, granted her the free passage of the Bosphorus and the Dardanelles, and promised to pay a war contribution of 137 million francs. In 1833 Mehemet Ali, Pasha of Egypt, who, not having been able to obtain the Morea through the Powers’ support, wanted to capture Syria, defeated the Turks at Konia and threatened Constantinople. The Tsar, Nicholas I, who hoped he could turn Turkey into a kind of Russian protectorate, then sent Mouraviev to Mahmoud to offer to put at his disposal a fleet and an army to fight with Mehemet Ali. A Russian fleet came and cast anchor before Constantinople, and a Russian detachment landed in the town. But then France, Austria, and Prussia, perhaps foreseeing the danger of a Russian occupation which might pave the way to a definite possession, asked the Sultan to make the necessary concessions to his vassal, and the latter to accept them. The treaty of Kutahia, signed on May 4, 1833, gave the Pasha of Egypt the whole of Syria and the province of Adana. Russia withdrew her troops, but did not lay down arms, and thus Count Orlov compelled the Porte to sign the treaty of Unkiar-i-Skelessi, which stipulated an offensive and defensive alliance between Russia and Turkey, and the closing of the Dardanelles to the other Powers. Turkey was now under Russian tutelage. After the defection of Ahmed Pasha, who led the Turkish fleet at Alexandria, Great Britain, lest Russia should establish her protectorate over Turkey, offered to France, through Lord Palmerston, to participate in a naval demonstration, but France declined the offer. Metternich then suggested a conference between the representatives of the five Great Powers, in order to substitute their guarantee for a Turkish protectorate. On July 27, 1839, the ambassadors handed the Sublime Porte a note communicating their agreement, and advising that no definite decision should be taken without their co-operation. Then England, having no further fear of Russian intervention, turned against Mehemet Ali, and Baron de Brunov even proposed an Anglo-Russian agreement.