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
Treaty of Stettin (1630) Pomerania to enforce Brandenburg's claims on succession, but they were defeated by Sweden in the ensuing battles. Some of the Pomeranian nobility had changed sides and supported Brandenburg. By the end of the war, the treaty was superseded by the Peace of Westphalia (1648) and the subsequent Treaty of Stettin (1653), when Pomerania was partitioned into a western, Swedish part (Western Pomerania, thenceforth Swedish Pomerania), and an eastern, Brandenburgian part (Farther Pomerania, thenceforth the Brandenburg-Prussian Province of Pomerania). Following the Capitulation of Franzburg in 1627, the Duchy of Pomerania was occupied by forces of Ferdinand II, Holy Roman Emperor, under