Duke Christian Charles of Schleswig-Holstein-Sonderburg-Plön-Norburg[1] (20 August 1674 – 23 May 1706 in Sonderburg) was an officer in the Brandenburg-Prussian army.
Christian Charles was the younger son of Duke Augustus of Schleswig-Holstein-Sonderburg-Plön-Norburg and Elisabeth Charlotte of Anhalt-Harzgerode.
After the death of his father, Duke Augustus, and the accession to power of his older brother Joachim Frederick in 1699, Christian Charles received only a paréage, consisting of the former dominions of his uncle Duke Bernhard of Schleswig-Holstein-Sonderburg-Plön: viz.
When his son, Frederick Charles, had become Duke of Schleswig-Holstein-Sonderburg-Plön after a long succession dispute, his body was transferred to the ducal crypt in Plön.
The morganatic and secretly contracted marriage led to an agreement with his reigning brother in which Christian Charles waived princely rights for his descendants and adopted the family name "von Karlstein".