Wallenstein or Waldstein, Albrecht Wenzel Eusebius von (wälˈənstĪn, Ger. älˈbrĕkht vĕnˈtsəl oizāˈbēŏs fən välˈənshtĪn, vältˈshtĪn) [key], 1583–1634, imperial general in the Thirty Years War, b. Bohemia. He attended the Lutheran academy at Altdorf but at the age of 20 converted to Roman Catholicism. He advanced his fortune by marriage to a wealthy widow, and for his support of Archduke Ferdinand of Styria (Holy Roman Emperor Ferdinand II) before, during, and after the Bohemian revolt that started the Thirty Years War, he was well rewarded, becoming prince and then (1625) duke of Friedland. He built up a magnificent estate in Bohemia, expanding his fortune at the expense of the Bohemian Protestants, whose lands he confiscated with Ferdinand's authorization. In 1625, Wallenstein raised a large army for Ferdinand II and became chief imperial general, cooperating with the general of the Catholic League, Count Tilly, in the Danish phase of the war. Wallenstein in 1626 defeated Ernst von Mansfeld at the Dessau bridgehead, and some of his men helped Tilly to defeat the Danish king Christian IV at Lutter. The next year Wallenstein destroyed the remnants of Mansfeld's army and later defeated Christian IV's forces. Now at the height of his wealth and power, Wallenstein, having driven the dukes of Mecklenburg from their lands, was granted that duchy as a hereditary fief from the Holy Roman emperor. He was also given the title of admiral, but his hopes of founding a maritime empire were set back by the failure of the siege of Stralsund (1628) on the Baltic. Wallenstein had powerful enemies, particularly among the German princes, from whom he had extorted money for the support of the army. Finally, in 1630, they prevailed on Ferdinand to dismiss him. The failure of his successor, Tilly, against King Gustavus II of Sweden brought Wallenstein back to power (1632). With a huge army he cleared Bohemia and began a contest with the Swedish king that ended at Lützen (1632), where Wallenstein was defeated and the Swedish king was killed. Embittered by his earlier dismissal, Wallenstein was then determined to become more powerful than ever, controlling not only military decisions, but imperial policy also. His secret negotiations with the enemy brought down on his head accusations of treason. A number of his generals, including Matthias Gallas and Ottavio Piccolomini, were drawn into a conspiracy against him. Ferdinand secretly removed Wallenstein from command on Jan. 24, 1634. Wallenstein renewed his attempts to negotiate with the Swedes and with a few hundred troops fled to Eger (Cheb), where he was treacherously murdered (Feb., 1634). His assassin later had the emperor's favor. Wallenstein is the central figure in a dramatic trilogy by Schiller.