Under King Philip II of Spain religious tensions came to the surface. The teachings of Calvin had taken hold and the Catholic king’s persecution of Protestantism was regarded by the lowlanders as a restriction on religious freedom. Even Dutch Catholics were outraged by the antics of the Spanish Inquisition. In 1568, the northern Dutch provinces revolted under Prince William of Orange, and so began a protracted battle for independence – the Eighty Years’ War. This ended in 1648 with the Peace of Westphalia and recognition of the United Provinces as an independent state. William of Orange Nassau (Catholic, Lutheran, Father of The Fatherlands) took the position of Stadtholder (provincial governor).