In February 1708, Charles himself was once more in Lithuania, at the head of an army.  But his advance towards Moscow was disputed at well-selected points, and even his victory at Hollosin was a proof that the Russians had now learned how to fight.

When Charles reached the Dnieper, he unexpectedly marched to unite with Mazeppa in the Ukraine, instead of continuing his advance on Moscow.  Menzikoff intercepted Lewenhaupt on the march with a great convoy to join Charles, and that general was only able to cut his way through with 5,000 of his force.  Mazeppa’s own movement was crushed, and he only joined Charles as a fugitive, not an ally.  Charles’s desperate operations need not be followed.  It suffices to say that in May 1709, he had opened the siege of Pultawa, by the capture of which he counted that the road to Moscow would lie open to him.

Here the decisive battle was fought on July 12.  The dogged patience with which Peter had turned every defeat into a lesson in the art of war met with its reward.  The Swedish army was shattered; Charles, prostrated by a wound, was himself carried into safety across the Turkish frontier.  Peter’s victory was absolutely decisive and overwhelming; and what it meant was the civilising of a territory till then barbarian.  Its effects in other European countries, including the recovery of the Polish crown by Augustus, are pointed out in the history of Charles XII.  The year 1710 witnessed the capture of a series of Swedish provinces in the Baltic provinces; and the Swedish forces in Pomerania were neutralised.

IV.—­The Expansion of Russia

Now the Sultan Ahmed III. declared war on Peter; not for the sake of his guest, Charles XII., but because of Peter’s successes in Azov, his new port of Taganrog, and his ships on the Sea of Azov and the Black Sea.  He outraged international law by throwing the Russian envoy and his suite into prison.  Peter at once left his Swedish campaign to advance his armies against Turkey.

Before leaving Moscow he announced his marriage with the Livonian captive, Catherine, whom he had secretly made his wife in 1707.  Apraksin was sent to take the supreme command by land and sea.  Cantemir, the hospodar of Moldavia, promised support, for his own ends.

The Turkish vizier, Baltagi Mehemet, had already crossed the Danube, and was marching up the Pruth with 100,000 men.  Peter’s general Sheremetof was in danger of being completely hemmed in when Peter crossed the Dnieper, Catherine stoutly refusing to leave the army.  No help came from Cantemir, and supplies were running short.  The Tsar was too late to prevent the passage of the Pruth by the Turks, who were now on his lines of communication; and he found himself in a trap, without supplies, and under the Turkish guns.  When he attempted to withdraw, the Turkish force attacked, but were brilliantly held at bay by the Russian rear-guard.