Prince Philip was not made king due to longstanding British royal tradition: when a man marries a Queen, he does not automatically take the male version of the title. Elizabeth II designated him a Prince and later Duke of Edinburgh; he never held the title of king. In short, the position was a matter of protocol and title rules, not personal choice. This is why his wife could be Queen, but he remained Duke (and later Prince) rather than King .[3][5]
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There's a reason that 'King consort' doesn't exist
www.goodto.comPRINCE PHILIP has been described as the Queen's "strength and stay". But despite being her most loyal companion, why is the Duke of Edinburgh not a King, or a King Consort?
www.express.co.ukWhy wasn’t Prince Philip a king? Prince Philip did not have the title of king because of British royal tradition whereby a man marrying into the royal
www.britannica.comWhen Philip Mountbatten married into the royal family way back in 1947, he became the Duke of Edinburgh along with a number of other titles.
www.standard.co.ukThe Duke of Edinburgh died on Friday at 99.
www.marieclaire.comThough he was married to a queen, he was named a prince for a reason
www.harpersbazaar.comPhilip was once the prince of Denmark and Greece, before marrying Queen Elizabeth nearly 74 years ago.
www.cbsnews.comQueen Elizabeth II and Prince Philip were together for 73 years but why was the Duke of Edinburgh never king but Camilla is Queen Consort?
royal-insider.com