Count Christian V of Oldenburg (died 1423) was the ruling count of Oldenburg

Oldenburg (state)

Oldenburg — named after its capital, the town of Oldenburg — was a state in the north of present-day Germany. Oldenburg survived from 1180 until 1918 as a county, duchy and grand duchy, and from 1918 until 1946 as a free state. It was located near the mouth of the River Weser...

 from 1398 until his death in 1423. He was born sometime before 1347 to Count Conrad I of Oldenburg and Ingeborg of Brunswick. He married Agnes of Honstein, and through his son and successor Count Dietrich of Oldenburg

Dietrich of Oldenburg

Derrick or Dietrich of Oldenburg, Latin-based anglicization also Theoderic of Oldenburg , nicknamed Theoderic the Lucky or the Fortunate , was a feudal lord in northern Germany, holding the counties of Delmenhorst and Oldenburg...

, descends the Danish Royal houses of Oldenburg

House of Oldenburg

The House of Oldenburg is a North German dynasty and one of Europe's most influential Royal Houses with branches that rule or have ruled in Denmark, Russia, Greece, Norway, Schleswig, Holstein, Oldenburg and Sweden...

 and Schleswig-Holstein-Sonderburg-Glücksburg

Schleswig-Holstein-Sonderburg-Glücksburg

The House of Schleswig-Holstein-Sonderburg-Glücksburg , known as the House of Glücksburg for short, is a German ducal house, junior branches of which include the royal houses of Denmark and Norway, the deposed royal house of Greece, and the heir to the thrones of the Commonwealth realms The House...

. Through the dynastic marriages of his descendants he is an ancestor of many European Royal houses.