Of course, this sudden growth of so dangerous a rival had been a source of great worry to all the neighbours. From his side, Peter had watched with interest the many adventures of his Baltic rival, the kingdom of Sweden. In the year 1654, Christina, the only daughter of Gustavus Adolphus, the hero of the Thirty Years War, had renounced the throne and had gone to Rome to end her days as a devout Catholic. A Protestant nephew of Gustavus Adolphus had succeeded the last Queen of the House of Vasa. Under Charles X and Charles XI, the new dynasty had brought Sweden to its highest point of development. But in 1697, Charles XI died suddenly and was succeeded by a boy of fifteen, Charles XII. This was the moment for which many of the northern states had waited. During the great religious wars of the seventeenth century, Sweden had grown at the expense of her neighbours. The time had come, so the owners thought, to balance the account. At once war broke out between Russia, Poland, Denmark and Saxony on the one side, and Sweden on the other. The raw and untrained armies of Peter were disastrously beaten by Charles in the famous battle of Narva in November of the year 1700. Then Charles, one of the most interesting military geniuses of that century, turned against his other enemies and for nine years he hacked and burned his way through the villages and cities of Poland, Saxony, Denmark and the Baltic provinces, while Peter drilled and trained his soldiers in distant Russia. As a result, in the year 1709, in the battle of Poltawa, the Moscovites destroyed the exhausted armies of Sweden. Charles continued to be a highly picturesque figure, a wonderful hero of romance, but in his vain attempt to have his revenge, he ruined his own country. In the year 1718, he was accidentally killed or assassinated (we do not know which) and when peace was made in 1721, in the town of Nystadt, Sweden had lost all of her former Baltic possessions except Finland. The new Russian state, created by Peter, had become the leading power of northern Europe. But already a new rival was on the way. The Prussian state was taking shape. THE RISE OF PRUSSIA THE EXTRAORDINARY RISE OF A LITTLE STATE IN A DREARY PART OF NORTHERN GERMANY, CALLED PRUSSIA The history of Prussia is the history of a frontier district. In the ninth century, Charlemagne had transferred the old centre of civilisation from the Mediterranean to the wild regions of northwestern Europe. His Frankish soldiers had pushed the frontier of Europe further and further towards the east. They had conquered many lands from the heathenish Slavs and Lithuanians who were living in the plain between the Baltic Sea and the Carpathian Mountains, and the Franks administered those outlying districts just as the United States used to administer her territories before they achieved the dignity of statehood.