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
Siege of Breda (1624) thereafter. The siege of 1624 captured the attention of European princes and, along with other battles like White Mountain (1620), played a part in the Spanish army regaining the formidable reputation it had held throughout the previous century. In the latter stages of the combined Eighty and Thirty Years' wars that had greatly strained Spanish resources, Breda was lost to the Dutch under Frederick Henry after a four-month siege. In the 1648 Treaty of Westphalia that ended the Thirty and Eighty Years' wars, it was ceded to the Dutch Republic. There were several motives for Spinola's siege of Breda. Because