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 Paris (1815) at accumulating interest for the benefit of the creditors. As soon as the inscription had been effected, Britain would restore the French colonies as agreed in the treaty of 1814, including the islands of Martinique and Guadeloupe, provisionally re-occupied by the British troops. The Swiss Confederation had been internationally recognised as an independent neutral state at the Peace of Westphalia in 1648. During the Napoleonic Wars it failed to remain neutral, as some cantons had been annexed into other states and, under French influence, the Act of Mediation was signed and the Swiss Confederation was replaced by the more centralised