and Hesse-Darmstadt also gained the Duchy of Westphalia from Cologne, the parts of Worms on the right-bank of the Rhine, and the former Free City of Friedberg. Nassau-Weilburg gained the right-bank territories of Trier among other territories. Orange-Nassau gained the Prince-Bishopric of Fulda (as the Principality of Nassau-Orange-Fulda). The Landgrave of Hesse-Kassel was also elevated to the status of Prince-Elector (), with his state thereby becoming the Electorate of Hesse or Electoral Hesse (, being the German-language term for the Empire's College of Electors). In July 1806 Hesse-Darmstadt, Nassau-Weilburg, Nassau-Usingen, and the newly-merged Principality of Isenburg became founding members of Napoleon's Confederation of the Rhine. Hesse-Darmstadt expanded further in the resulting mediatisation, absorbing numerous small states (including Hesse-Homburg and much of the territory of the Houses of , and Sayn-Wittgenstein). It was also elevated by Napoleon to the status of Grand Duchy, becoming the Grand Duchy of Hesse. Orange-Nassau, which refused to join the Confederation, lost Siegen, Dillenburg, Hadamar and Beilstein to Berg and Fulda to the Prince-Primate of the Confederation (and former Elector of Mainz) Karl Theodor von Dalberg; the remainder of its territory was merged with that of Nassau-Usingen and Nassau-Weilburg in August 1806 to form the Duchy of Nassau. Waldeck also joined the Confederation in 1807. The Holy Roman Empire was dissolved in August 1806, rendering Hesse-Kassel's electoral privilege meaningless. Hesse-Kassel was occupied by the French in October 1806 and the remainder of Lower Katzenelnbogen was annexed to the French Empire as . The rest of its territory was annexed to the Kingdom of Westphalia in 1807; Hesse-Hanau (a secundogeniture of Hesse-Kassel) was annexed to the Grand Duchy of Frankfurt in 1810 along with the other territories held by the Prince-primate: Frankfurt, Fulda, Aschaffenburg and Wetzlar. As a result of the German campaign of 1813 the Kingdom of Westphalia and the Grand Duchy of Frankfurt were dissolved and Hesse-Kassel and Hesse-Hanau were restored; Orange-Nassau was also restored in its territories previously lost to Berg. As a result of the 1815 Congress of Vienna Hesse-Kassel gained Fulda (roughly the western third of the former Prince-Bishopric, the rest of which went to Bavaria and Saxe-Weimar-Eisenach) from Frankfurt and part of Isenburg, while several of its small northern exclaves were absorbed into Hanover, some small eastern areas were ceded to Saxe-Weimar-Eisenach and Lower Katzenelnbogen was ceded to Nassau. Hesse-Darmstadt lost the Duchy of Westphalia and the Sayn-Wittgensteiner lands to the