Gustavus Adolphus (Gustavus II.), king of Sweden from 1611 to 1632, was born at Stockholm, December 9, 1594, the son of Charles IX., and grandson of the great Gustavus Vasa. He was carefully educated, and grew up one of the most accomplished princes of his age. He knew eight languages, speaking and writing five of these with fluency, was well read in the classics and ancient history, proficient in music, and skilful in all manly exercises. When he came to the throne in his eighteenth year he found the country involved in wars abroad and disorders at home, arising from the disputed succession of his father, who had been elected king to the exclusion of the direct heir, his nephew, the Roman Catholic Sigismund, king of Poland. The first act of Gustavus was to secure the hearty co-operation of the nobles, by confirming their privileges subject to the performance of military service to the crown. Having reorganised the internal government, and raised both men and money, he made war on Denmark, and soon recovered his Baltic provinces, and a direct outlet towards Russia. His war with Russia was ended in 1617, by the treaty of Stolbova, by which Sweden obtained supreme dominion over Ingermanland and Karelia, and part of Livonia, while Russia recovered Novgorod and all other conquests made by the Swedes. In 1618 Gustavus visited Berlin in secret and fell in love with the strong-minded daughter of the Elector of Brandenburg, whom two years later he married. On that second visit in 1620 he traversed Germany as far south as Heidelberg. He next turned more actively to the intermittent dispute with Poland, which was at length terminated in 1629 by a six years' truce, which secured reciprocity of trade and freedom of religion to the natives of both countries, and left Gustavus master of Elbing, Braunsberg, Pillau, and Memel.
This peace enabled the king to mature the plans he had long cherished in regard to Germany, and accordingly, after making various administrative reforms at home, he remitted the charge of the government and the care of his infant daughter Christina to his chancellor Oxenstiern, and crossed to Pomerania about the midsummer of 1630, with but 15,000 men, to head the Protestants of Germany in their hard struggle against the Catholic League, which was backed by all the power of the empire and the restless arms of Tilly and Wallenstein.
Everything favoured the success of the Swedes, who drove the imperialists from Pomerania, and took Stettin. The Duke of Pomerania, the aged Boguslaw, last of the old Wendish line, engaged, in return for Swedish aid, that the dukedom should, after his death, be given up to Sweden until the expenses of the war were fully repaid; whilst Richelieu promised Gustavus a substantial subsidy as long as he maintained an army of 36,000 men. The Emperor Ferdinand had been obliged by the Electors to dismiss the imperious Wallenstein from his service. But, while the Swedes were besieging Spandau and Küstrin, the rich city of Magdeburg, which had applied for help to Gustavus, who could not move without the support of the hesitating Electors of Brandenburg and Saxony, was taken by Tilly. His troops perpetrated the most terrible atrocities upon the citizens, and all the buildings were burned to the ground save the cathedral alone. The Protestant German princes had been slow in coming in to Gustavus; but after John George of Saxony was driven into his arms by the impolitic demands of Ferdinand, Gustavus came more and more to be identified as the champion of their religion against oppression. Meanwhile the unselfishness of his own aims and his elevation of character, as well as the admirable discipline and the conduct of his hardy veterans in such strong contrast to the ungoverned license of the imperial troops, gained the confidence and admiration of all Germany. Soon after the fall of Magdeburg, Gustavus inflicted a severe defeat on Tilly at Breitenfeld, which taught the Catholics to fear the 'snow-king' and his body- guard,' as they designated Gustavus and his small army. The king now advanced into Franconia, and, after allowing his army to recruit their strength in the rich bishoprics of Würzburg and Bamberg, took the Palatinate and Mainz, where he held a splendid court, surrounded by numerous princes and ambassadors. In the April of 1632 the Swedes, in the face of Tilly's army, crossed the Lech and gained a decisive victory, whence Tilly was carried to Ingolstadt to die. From thence the march to Munich was one continued triumph, and wherever Gustavus appeared he was received by the populace as their guardian angel. The road to Vienna was now open to him, and the fate of the emperor would have been sealed had the latter not recalled his haughty general, Wallenstein, who, having accepted office on his own terms, gathered together a large and heterogeneous army of 60,000 men, and advanced on Nuremberg, where he entrenched himself strongly. After withstanding a desperate assault of the Swedes he was obliged to retire into Thuringia. The unfavourable season, the bad roads, and the cautious dispositions of Wallenstein hindered Gustavus from attacking the imperialists as soon as he intended, but on November 6, 1632, the two armies came finally face to face at Lützen, ten miles to the south-west of Leipzig. A thick fog lay close upon the ground. The Swedes gathered to morning prayer to the music of Luther's noble hymn, 'Eine feste Burg ist unser Gott.' About eleven the mist cleared off, and Gustavus gave his last orders to his generals. Waving his sword above his head he cried 'Forwards,' and rode to meet the enemy at the head of the cavalry on the right wing. His eager troops soon broke the imperial lines, but Wallenstein bringing up his reserves drove back the Swedish infantry in the centre. Gustavus hastened too eagerly to the rescue, and, in the thick fog which had again descended, was separated from the cavalry he had ordered to follow him, and rode almost alone into a squadron of Croats. A shot passed through his horse's neck, another shattered his left arm, a third struck him in the back, and he fell heavily to the ground. A cuirassier riding up asked who was there. 'I was the king of Sweden,' murmured the dying king, whereupon the soldier shot him through the head. Bernhard of Weimar took up the command, while on the enemy's side Pappenheim's cavalry came up to take their part in the battle. The Swedes burned to revenge their king and fought with a fury that was irresistible. Hour after hour the battle swayed uncertainly, till at length, when Pappenheim had fallen and his artillery had been taken, Wallenstein drew his men off the field and left their hard-won victory to the Swedes. The body of Gustavus was recovered and laid to rest in the Riddarholm church at Stockholm.
So fell the great hero of the Thirty Years' War, and with him perished all hope of a speedy ending to the fatal struggle, and the establishment of a durable peace in Germany. His Corpus Evangelicorum was a noble imagination, and would have built up a Protestant power around the shores of the Baltic so strong as to defy all attack. But it is more than probable that a foreigner even so disinterested as himself might have failed to overcome the instinctive cohesiveness of even a divided Germany, and if so, he was happy in the accident of death on the field of victory, leaving behind him a deathless glory undimmed by failure.
See books on Gustavus Adolphus by J. L. Stevens (1885), Trench (new ed. 1886), C. R. L. Fletcher (1890), Colonel R. A. Dodge (New York, 1896), and other works cited at THIRTY YEARS' WAR.