It was this fatal promise, which was never to be kept, that probably lured Charles to his ruin. After a long and disastrous campaign he met his final crushing defeat at Poltova in 1709. The King and Mazeppa, companions in flight, together entered the Sultan's dominions as fugitives, and of the army before which a short time ago Europe had trembled--there was left not one battalion. The Baltic was passing into new hands. "The window" opening upon the West was to become a door, and the key of the door was to be kept upon the side toward Russia! Sweden, which under Gustavus Adolphus, Charles XI., and Charles XII. had played such a glorious part, was never to do it again; and the place she had left vacant was to be filled by a new and greater Power. Russia had dispelled the awakened dream of a great Scandinavian Empire and--so long excluded and humiliated--was going to make a triumphal entry into the family of European nations. The Tsar, with his innovations and reforms, was vindicated. For breadth of design and statesmanship there was not one sovereign in the coalition who could compare with this man who, Bishop Burnet thought, was better fitted for a mechanic than a Prince--and "incapable of a great enterprise." Of Charles XII. it has been said that "he was a hero of the Scandinavian Edda set down in the wrong century," and again that he was the last of the Vikings, and of the Varangian Princes. But Mazeppa said of him, when dying in exile: "How could I have been seduced in my old age by a military vagabond!"