Gustavus II (1594-1632) was king of Sweden from 1611 to 1632. He did much to make Sweden a major European power, and his military exploits were highly important in the history of Russia, Germany, Poland, and the Baltic Provinces.

The eldest son of Charles IX of Sweden and Christina of Holstein-Gottorp, Gustavus II was born on Dec. 9, 1594. Although his parents had Calvinist leanings, Gustavus received heavy doses of Lutheranism. History, government, warfare, and engineering were among the subjects he pursued, with special emphasis on language. Count Axel Oxenstierna, his most trusted adviser, said of his sovereign, "In his youth he obtained a thorough knowledge and perfect command of many foreign tongues, so that he spoke Latin, German, Dutch, French, and Italian like a native, understood Spanish, English, and Scotch, and had besides some notion of Polish and Russian." At 9 Gustavus was introduced into public life, and at 13 he was receiving...