House of Oldenburg

The House of Oldenburg is a German dynasty with links to Denmark since the 15th century. It has had branches that rule or have ruled in Denmark, Iceland, Greece, Norway, Russia, Sweden, the United Kingdom, Schleswig, Holstein, and Oldenburg. The current Queen of Denmark, King of Norway and King of the United Kingdom are all patrilineal descendants of the Glücksburg branch of this house.

Glücksburg is the senior surviving branch of the Oldenburg dynasty, it's only surviving other branch is the House of Holstein-Gottorp.