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
Seventeen Provinces during the Eighty Years' War (see Generality Lands), which ended with the Treaty of Westphalia in 1648. Artois and parts of Flanders and Hainaut (French Flanders and French Hainaut) were ceded to France in the course of the 17th and 18th centuries. By the mid-16th century, the Margraviate of Antwerp (Duchy of Brabant) had become the economic, political, and cultural center of the Netherlands after its capital had shifted from the nearby Lordship of Mechelen to the city of Brussels. Bruges (County of Flanders) had already lost its prominent position as economic powerhouse of northern Europe. And Holland was gradually