Karl III August Christian, Count Palatine of Birkenfeld-Zweibrücken

Charles II August
Duke of Zweibrücken
Charles II, Duke of Zweibrücken
Born	(1746-10-29)29 October 1746 Düsseldorf
Died	1 April 1795(1795-04-01) (aged 48) Mannheim
Spouse	Maria Amalia of Saxony
Issue	Charles Augustus Fredrick
House	Palatinate-Zweibrücken-Birkenfeld
Father	Frederick Michael, Count Palatine of Birkenfeeld-Bishwiller-Rappolstein
Mother	Maria Franziska of Sulzbach
Religion	Roman Catholicism

Charles II August Christian (German: Karl II. August Christian; 29 October 1746 – 1 April 1795) was Duke of Zweibrücken from 1775 to 1795. A member of the Palatine House of Zweibrücken-Birkenfeld, a branch of the House of Wittelsbach, he was the elder brother of the first King of Bavaria, Maximilian I, and of Queen Amalia of Saxony.

Charles was born in Düsseldorf, the oldest of five children of Frederick Michael, Count Palatine of Birkenfeld-Bishwiller-Rappoltstein and Countess Palatine Maria Franziska of Sulzbach. His father converted to his mother's Roman Catholic faith shortly after his birth, he and his siblings being raised in that denomination. He inherited the duchy of Zweibrücken from his paternal uncle, Duke Christian IV, in 1775. He was heir presumptive to his childless cousin Charles Theodore, Elector of Bavaria whom, however, he predeceased. He ceded to his younger brother Maximilian Joseph the county of Rappoltstein in 1776, having inherited it when their father died in 1767.

He wanted to marry Archduchess Maria Amalia of Austria, the eighth child of Empress Maria Theresa. He was well known in the Austrian court, and Maria Amalia was also in love with him. However, Maria Theresa deemed him of insufficient rank to marry an archduchess. Moreover, she wanted to strengthen Austria's alliance with the House of Bourbon by marrying a daughter to Ferdinand, Duke of Parma, a grandson of the French king, Louis XV. This was to be Maria Amalia, due to the death of another daughter, Maria Josepha.