Brandenburg-Prussia Catholic armies swept the land back and forth, killing, burning, seizing men and taking the food supplies. Upwards of half the population was killed or dislocated. Berlin and the other major cities were in ruins, and recovery took decades. By the Peace of Westphalia, which ended the Thirty Years' War in 1648, Brandenburg gained Minden and Halberstadt, also the succession in Farther Pomerania (incorporated in 1653) and the Duchy of Magdeburg (incorporated in 1680). With the Treaty of Bromberg (1657), concluded during the Second Northern War, the electors were freed of Polish vassalage for the Duchy of Prussia and gained
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