Bassaraba Brancovan had been invested with the principality of Walachia, but had not found any genealogist to deduce his pedigree from the Tartarian conqueror. Cantemir thought the time now come to shake off the Turkish yoke, and render himself independent by means of the czar's protection. In this view he acted in the very same manner with Peter as Mazeppa had done with Charles XII. He even engaged Bassaraba for the present to join him in the conspiracy, of which he hoped to reap all the benefit himself: his plan being to make himself master of both provinces. The bishop of Jerusalem, who was at that time at Walachia, was the soul of this conspiracy. Cantemir promised the czar to furnish him with men and provisions, as Mazeppa did the king of Sweden, and kept his word no better than he had done.

General Sheremeto advanced towards Jassi, the capital of Moldavia, to inspect and occasionally assist the execution of these great projects. Cantemir came thither to meet him, and was received with all the honours due to a prince: but he acted as a prince in no one circumstance, but that of publishing a manifesto against the Turkish empire. The hospodar of Walachia, who soon discovered the ambitious views of his colleague, quitted his party, and returned to his duty. The bishop of Jerusalem dreading, with reason, the punishment due to his perfidy, fled and concealed himself: the people of Walachia and Moldavia continued faithful to the Ottoman Porte, and those, who were to have furnished provisions for the Russian army, carried them to the Turks.

The vizier, Baltagi Mahomet had already crossed the Danube, at the head of one hundred thousand men, and was advancing towards Jassi, along the banks of the river Pruth (formerly the Hierasus), which falls into the Danube, and which is nearly the boundary of Moldavia and Bessarabia. He then dispatched count Poniatowsky,[87] a Polish gentleman, attached to the fortunes of the king of Sweden, to desire that prince to make him a visit, and see his army. Charles, whose pride always got the better of his interest, would not consent to this proposal: he insisted that the grand vizier should make him the first visit, in his asylum near Bender. When Poniatowsky returned to the Ottoman camp, and endeavoured to excuse this refusal of his master, the vizier, turning to the khan of the Tartars, said, 'This is the very behaviour I expected from this proud pagan.' This mutual pride, which never fails of alienating the minds of those in power from each other, did no service to the king of Sweden's affairs; and indeed that prince might have easily perceived, from the beginning, that the Turks were not acting for his interest, but for their own.

While the Turkish army was passing the Danube, the czar advanced by the frontiers of Poland, and passed the Boristhenes, in order to relieve marshal Sheremeto, who was then on the banks of the Pruth, to the southward of Jassi, and in danger of being daily surrounded by an army of ten thousand Turks, and an army of Tartars. Peter, before he passed the Boristhenes, was in doubt whether he should expose his beloved Catherine to these dangers, which seemed to increase every day; but Catherine, on her side, looked upon this solicitude of the czar, for her ease and safety, as an affront offered to her love and courage; and pressed her consort so strongly on this head, that he found himself under a necessity to consent that she should pass the river with him. The army beheld her with eyes of joy and admiration, marching on horseback at the head of the troops, for she rarely made use of a carriage. After passing the Boristhenes, they had a tract of desert country to pass through, and then to cross the Bog, and afterwards the river Tiras, now called the Niester, and then another desert to traverse, before they came to the banks of the Pruth. Catherine, during this fatiguing march, animated the whole army by her cheerfulness and affability. She sent refreshments to such of the officers who were sick, and extended her care even to the meanest soldier.

July 4, 1711.] At length the czar brought his army in sight of Jassi. Here he was to establish his magazine. Bassaraba, the hospodar of Walachia, who had again embraced the interest of the Ottoman Porte, but still, in appearance, continued a friend to the czar, proposed to that prince to make peace with the Turks, although he had received no commission from the grand vizier for that purpose. His deceit, however, was soon discovered; and the czar contented himself with demanding only provisions for his army, which Bassaraba neither could nor would furnish. It was very difficult to procure any supplies from Poland; and these, which prince Cantemir had promised, and which he vainly hoped to procure from Walachia, could not be brought from thence. These disappointments rendered the situation of the Russian army very disagreeable; and, as an addition to their afflictions, they were infested with an immense swarm of grasshoppers, that covered the face of the whole country, and devoured, or spoiled, every thing where they alighted. They were likewise frequently in want of water during their march through sandy deserts, and beneath a scorching sun: what little they could procure, they were obliged to have brought in vessels to the camp, from a considerable distance.

During this dangerous and fatiguing march, the czar, by a singular fatality, found himself in the neighbourhood of his rival and competitor, Charles; Bender not being above twenty-five leagues from the place where the Russian army was encamped, near Jassi. Some parties of Cossacks made excursions even to the place of that unfortunate monarch's retreat; but the Crim Tartars, who hovered round that part of the country, sufficiently secured him from any attempt that might be made to seize his person; and Charles waited in his camp with impatience, and did not fear the issue of the war.

Peter, as soon as he had established some magazines, marched in haste with his army to the right of the river Pruth. His essential object was to prevent the Turks, who were posted to the left, and towards the head of the river, from crossing it, and marching towards him. This effected, he would then be master of Moldavia and Walachia: with this view, he dispatched general Janus, with the vanguard of the army, to oppose the passage of the Turks; but the general did not arrive till they had already began to cross the river upon their bridges; upon which he was obliged to retreat, and his infantry was closely pursued by the Turks, till the czar came up in person to his assistance.

The grand vizier now marched directly along the river towards the czar. The two armies were very unequal in point of numbers: that of the Turks, which had been reinforced by the Tartarian troops, consisted of nearly two hundred and fifty thousand men, while that of the Russians hardly amounted to thirty-five thousand. There was indeed a considerable body of troops, headed by general Renne, on their march from the other side of the Moldavian mountains; but the Turks had cut off all communication with those parts.

The czar's army now began to be in want of provisions, nor could, without the greatest difficulty, procure water, though encamped at a very small distance from the river; being exposed to a furious discharge from the batteries, which the grand vizier had caused to be erected on the left side of the river, under the care of a body of troops, that kept up a constant fire against the Russians. By this relation, which is strictly circumstantial and true, it appears that Baltagi Mahomet, the Turkish vizier, far from being the pusillanimous, or weak commander, which the Swedes have represented him, gave proofs, on this occasion, that he perfectly well understood his business. The passing the Pruth in the sight of the enemy, obliging him to retreat, and harassing him in that retreat; the cutting off all communication between the czar's army, and a body of cavalry that was marching to reinforce it; the hemming in this army, without the least probability of a retreat; and the cutting off all supplies of water and provisions, by keeping it constantly under the check of the batteries on the opposite side of the river, were manœuvres that in no ways bespoke the unexperienced or indolent general.

Peter now saw himself in a situation even worse than that to which he had reduced his rival, Charles XII. at Pultowa; being, like him, surrounded by a superior army, and in greater want of provisions; and, like him, having confided in the promises of a prince, too powerful to be bound by those promises, he resolved upon a retreat; and endeavoured to return towards Jassi, in order to choose a more advantageous situation for his camp.