Westphalia to be Catholic. Osnabrück was divided almost equally between Catholicism and Protestantism. Parts of Westphalia came under Brandenburg-Prussian control during the 17th and 18th centuries, but most of it remained divided by duchies and other areas of feudal 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". After the defeat of the Prussian Army by the French at the Battle of Jena–Auerstedt, the Treaty of Tilsit in 1807 made the easternmost portion of today's Westphalia part of the
Treaty of Teschen margraviates in 1791. The Electorate of Saxony received a sum of six million guilders (florins) from Bavaria in exchange of its inheritance claims. With the accession of Elector Charles Theodore, the electorates of Bavaria and the County Palatine of the Rhine (i.e. the territories in the Rhenish Palatinate and the Upper Palatinate) were under the united rule of the House of Wittelsbach. Their electoral votes were combined into one per a provision in the earlier Treaty of Westphalia in 1648, thereby reducing the number of electorates in the Holy Roman Empire to eight. The Innviertel, except for a short time