King Christian, who in the meantime had lost his battles with the veteran Tilly, was forced to withdraw from the field. The time now seemed ripe for action. England and Holland were willing to submit to the plans of Gustavus Adolphus. The Protestant princes requested him to become “the defender of their heritage”, and Richelieu advised him to take an active part in the contest. He negotiated with England, Holland and France, but with little result, as they gave evasive and indefinite answers. He was now fully determined, however, to enter the lists--it was a case of averting a future danger from his own kingdom--and in the autumn of 1629 he called a meeting of the council of state. This session became a turning point in modern history. It was decided that Sweden should take an active part in the Thirty Years’ War.[2] After large preparations Gustavus Adolphus set sail for Germany in June, 1630, with a picked army of about 13,000 men. He at once turned the tide of events. He rescued the Reformation and raised Sweden to a first class power in European politics, but his brilliant career was cut short on the memorable battlefield of Lützen in November, 1632. The government was now placed in the hands of “the five high officers of the kingdom”, until Christina became of age, and the war went on. Success continued for a time to follow the Swedish forces, but the spell of invincibility deserted them at Nördlingen in 1634; and the two following years were dark and full of trials for the Swedish leaders, interrupted only by a few brilliant achievements of Johan Banér. Gradually, however, the sky brightened. Swedish statesmen like Oxenstierna and Brahe and Swedish generals like Banér and Torstensson wrought success of what appeared to be disaster. Denmark had kept aloof from an active participation in the Thirty Years’ War since 1629. She had seen the increasing influence and power of Sweden and her growing commercial interests and far reaching plans with envious eyes. Only one-third of the Swedish export and import trade, it was true, for the years 1637–1643 was carried on Swedish vessels; but Swedish ships had been sent to other continents, the Swedish flag was waving over possessions in the New World, and indications were that the mastery of the Baltic would soon pass over to the power lying north of Öresund. King Christian IV endeavored to assert and sustain Danish supremacy in the Baltic and Danish jurisdiction in the Sound. A heavy toll (amounting to over $3,000,000 in 1639) was collected from vessels passing through the Strait, a large part of which was levied on Swedish merchandise. Besides, Swedish vessels were often confiscated, and the Danish king conducted a regular warfare in everything but in name against his neighbor. In the peace negotiations of Sweden, Denmark also played the false friend.