European Union law fair dealing through their business. In 1517, the Protestant Reformation triggered a hundred years of crisis and instability. Martin Luther nailed a list of demands to the church door of Wittenberg, King Henry VIII declared a unilateral split from Rome with the Act of Supremacy 1534, and conflicts flared across the Holy Roman Empire until the Peace of Augsburg 1555 guaranteed each principality the right to its chosen religion ("cuius regio, eius religio"). This unstable settlement unravelled in the Thirty Years' War (1618–1648), killing around a quarter of the population in central Europe. The Treaty of Westphalia 1648, which brought
History of the Lands of the Bohemian Crown (1526–1648) German territory. Czechs fought on all sides: most of the rebellious Czech generals joined Protestant armies; Albrecht of Wallenstein was the most prominent Czech defector to the imperial cause. Bohemia served as a battlefield throughout the war. Prince Bethlen Gabor's Hungarian forces, reinforced by Turkish mercenaries, fought against the emperor and periodically devastated Slovakia and Moravia. Protestant German armies and, later, Danish and Swedish armies, laid waste the Czech provinces. Cities, villages, and castle fortresses were destroyed. Lusatia was incorporated into Saxony in 1635. In 1648 the Treaty of Westphalia confirmed the incorporation of the Bohemian Kingdom into the Habsburg