A period of almost incessant battles and sieges followed. Few men in history have given greater surprises to their age than Carl X; few, perhaps none, have accomplished equal results with the same means and in so short a time. In twelve months Poland lay bleeding at his feet, destined never to regain her former power. Russia, Austria and Denmark attacked him almost simultaneously, but by a march over a frozen sea, one of the greatest feats on record, he led his army into the heart of Denmark, compelling this power to sue for a peace, that gave to Sweden the most valuable territorial acquisition in her history. The great warrior king, however, soon broke the peace, the total annihilation of Denmark being his aim, but fortune failed him for the first time. Cromwell, on whose influence he had relied, died, changing the attitude of the commander of the English fleet; France fell off, the Netherlands took sides with the enemy, and the Danish people were aroused to fight for their existence. In the midst of tremendous activities, the King became ill during a diet in the beginning of 1660, and on the morning of February 13 he died, at the age of thirty-eight. II. Through these wars and through her efforts to extend her power, her commerce and her trade, Sweden came in contact with the outside world to a degree unknown in her previous history since the Viking age. Swedish statesmen wove a network of diplomatic connections, which brought their country in touch with almost every important nation in the world, and the government at Stockholm stretched the webs of its diplomacy to Holland, England, France, Russia, Spain, Portugal, the German States and even to Venice, Italy, Persia and Turkey. Sweden’s political and commercial relations with foreign countries concern us little in this treatise except those of Portugal, Spain, Denmark, England and Holland. Those of the three former nations will be touched upon as occasion demands, but those of the two latter (being the most important for an understanding of the commercial and political successes and failures of the Swedes during this period) need a brief sketch here.