The Holy Roman Emperor Ferdinand II provoked this terrible conflict in Central Europe by attempting, as King of Bohemia, to impose Catholicism within his dominions, triggering the ‘defenestration of Prague’ (1618), when his representatives were thrown out of the windows of Prague Castle. His outraged subjects offered his crown to the Calvinist Frederick, Elector of Palatinate. The war then detonated through a series of alliances and counter-alliances. The Ottomans joined Protestant Prince Bethlen of Hungary; Spain weighed in for Ferdinand, their General Spinola ravaging the Palatinate and capturing Breda (1625). The Catholic General Tilley triumphed at White Mountain (1620), and General Wallenstein at Lutter (1628). By 1629 Catholic triumph beckoned and the Protestant cause in the Thirty Years’ War seemed doomed. Catholic armies led by Generals Wallenstein and Tilly had rampaged over the territory of the Protestants’ main external champion, Christian IV of Denmark, forcing him to ignominious peace (the Treaty of Lubeck). Meanwhile, their nemesis, Holy Roman Emperor Ferdinand II, sought religious reclamation of territories that had converted to Lutheranism.
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