Eugene's main reason for desiring peace in the west was the growing danger posed by the Turks in the east. Turkish military ambitions had revived after 1711 when they had mauled Peter the Great's army on the river Pruth (Pruth River Campaign): in December 1714 Sultan Ahmed III's forces attacked the Venetians in the Morea. To Vienna it was clear that the Turks intended to attack Hungary and undo the whole Karlowitz settlement of 1699. After the Porte rejected an offer of mediation in April 1716, Charles VI despatched Eugene to Hungary to lead his relatively small but professional army. Of all Eugene's wars this was the one in which he exercised most direct control; it was also a war which, for the most part, Austria fought and won on her own.Eugene left Vienna in early June 1716 with a field army of between 80,000 and 90,000 men. By early August 1716 the Ottoman Turks, some 200,000 men under the sultan's son-in-law, the Grand Vizier Damat Ali Pasha, were marching from Belgrade towards Eugene's position west of the fortress of Petrovaradin on the north bank of the Danube. The Grand Vizier had intended to seize the fortress; but Eugene gave him no chance to do so. After resisting calls for caution and forgoing a council of war, the Prince decided to attack immediately on the morning of 5 August with approximately 70,000 men. The Turkish janissaries had some initial success, but after an Imperial cavalry attack on their flank, Ali Pasha's forces fell into confusion. Although the Imperials lost almost 5,000 dead or wounded, the Turks, who retreated in disorder to Belgrade, seem to have lost double that amount, including the Grand Vizier himself who had entered the mêlée and subsequently died of his wounds.