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. The current Queen of Denmark, the King of Norway and the ex-King of Greece as well as consorts of Spain, Greece and the United Kingdom belong to this Royal House.
It rose to prominence when Count Christian I of Oldenburg was elected King of Denmark in 1448, and of Norway in 1450. The house has occupied the Danish throne ever since. It was briefly poised to claim the thrones of England and Scotland through the marriage of the Stuart Princess Anne (later Queen) to Prince George of Denmark and Norway; however, following the early death of their only heir, Prince William, Duke of Gloucester, the line of succession passed to the House of Hanover.
The coat-of-arms of Oldenburg is that associated with the state of Oldenburg, a county, duchy and grand duchy, that existed between 1180 and 1918.