Prince Philip's death certificate has revealed the 99-year-old died of "old age".
Her Majesty's husband passed away "peacefully" at Windsor Castle on 9 April and according to the document, his death was certified by Sir Huw Thomas, head of the royal medical household.
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"Old age" is an accepted term if the patient is over 80 years old and the doctor signing the certificate has "personally cared for the deceased over a long period and has observed a gradual decline in his general health," according to guidance given to doctors completing certificates of cause of death in England and Wales.
The Duke of Edinburgh's death was registered on 13 April, four days after his passing, with the Royal Borough of Windsor and Maidenhead by his private secretary, Brigadier Archie Miller-Bakewell, who attended the funeral.
The Duke's funeral took place on 17th April
The document lists his full name as: "His Royal Highness The Prince Philip, Duke of Edinburgh formerly known as Prince Philippos of Greece and Denmark formerly known as Philip Mountbatten."
His first occupation is listed as "Naval Officer," while his second is "husband of Her Majesty Queen Elizabeth II, The Sovereign".
Prince Philip passed away nearly a month ago, and Buckingham Palace announced the sad news with a statement that read: "It is with deep sorrow that Her Majesty The Queen has announced the death of her beloved husband, His Royal Highness The Prince Philip, Duke of Edinburgh. His Royal Highness passed away peacefully this morning at Windsor Castle. The Royal Family join with people around the world in mourning his loss. Further announcements will be made in due course."
His funeral took place eight days later and was attended by only 30 people, including his grandson Prince Harry, who flew in from Los Angeles without his wife Meghan Markle, who is heavily pregnant and was advised not to travel by her doctors.