North Rhine–Westphalia power. The Peace of Westphalia of 1648, signed in Münster and Osnabrück, ended the Thirty Years' War. The concept of nation-state sovereignty resulting from the treaty became known as "Westphalian sovereignty". As a result of the Protestant Reformation, there is no dominant religion in Westphalia. Roman Catholicism and Lutheranism are on relatively equal footing. Lutheranism is strong in the eastern and northern parts with numerous free churches. Münster and especially Paderborn are thought of as Catholic. Osnabrück is divided almost equally between Catholicism and Protestantism. After the defeat of the Prussian Army at the Battle of Jena-Auerstedt, the Treaty of
Treaty of Xanten in Westphalia to be governed by the House of Hohenzollern, and were the oldest constituents of the future Prussian Rhineland and the future Province of Westphalia. Treaty of Xanten The Treaty of Xanten () was signed in the Lower Rhine town of Xanten on November 12, 1614 between Wolfgang Wilhelm, Count Palatine of Neuburg and John Sigismund, Elector of Brandenburg, with representatives from England and France serving as mediators. The treaty ended the War of the Jülich Succession and all hostilities between Wolfgang William and John Sigismund. Based on the terms of the treaty, the territories of Jülich-Berg and Ravenstein