Duke Constantine Frederick Peter of Oldenburg was the youngest son of Duke Peter Georgievich of Oldenburg and his wife, Princess Therese of Nassau-Weilburg. Known in the court of Emperor Nicholas II as Prince Constantine Petrovich Oldenburgsky, he was the father of the Russian Counts and Countesses von Zarnekau.
- Occupation
- military personnel
- Citizenship
- Russian Empire
- Born
- May 9, 1850
- Died
- March 18, 1906