Karlsberg Castle

Karlsberg Castle (German: Schloss Karlsberg) is a castle ruin on Buchenberg east of Homburg in Saarland, Germany. The castle was constructed from 1778 to 1788 in Baroque and Classical style by Johann Christian von Mannlich, architect and general building director of the dukes of Zweibrücken, by order of Charles II August, Duke of Zweibrücken. The castle was the largest country palace of Europe and served as the residence of the Duke of Zweibrücken. In 1793 the castle was destroyed by French revolutionary troops.

Charles II August was the son of the (titular) Count Palatine and prince of Palatinate-Zweibrücken and Palatinate-Birkenfeld-Bischweiler Frederick Michael. This means, his father was the head of the house Palatinate-Birkenfeld-Bischweiler, a side branch of the house Palatinate-Zweibrücken-Birkenfeld, which was a side branch of the ducal house of Palatinate-Zweibrücken, which itself was a side branch of the house of Wittelsbach-Palatinate, which held the title of elector Palatinate of the Rhine and was the Protestant branch of the house of Wittelsbach.

His upbringing as the son of an unimportant poor prince did not give Charles II August the chance to build a castle of European standing. It was the extinction of the three main branches of the house of Wittelsbach, which gave him the opportunity to do so. In 1775 Christian IV, duke of Zweibrücken died without legitimate children. Charles August became his successor. At the same time, neither Charles Theodore, Elector of Bavaria, Elector Palatine, the head of the Protestant main branch of the house of Wittelsbach, nor Maximilian III Joseph, Elector of Bavaria, the head of the Catholic main branch of the house of Wittelsbach, had surviving legitimate children. So Charles August was expected to succeed these relatives too.

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