Although Prince Charles is first-in-line to the throne and therefore set to become the King and the head of the Commonwealth following the passing of his mother, the Queen, the Prince of Wales might not become King Charles III, but instead take on a different name altogether.
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According to former Buckingham Palace spokesperson and author of On Duty with the Queen, Dickie Arbiter, Charles could choose another of his middle names to use as King. Speaking previously to HELLO! in 2018, he said: "He might choose one of his other names Philip, Arthur or George."
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This isn't an uncommon practice among British Kings and Queens. Her Majesty's father's first name was Albert, but he chose to go by King George VI, and King Edward VII's first name was also Albert.
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Meanwhile, although King Edward VIII kept his Christian name, he was always known to his family and friends as David, his last middle name.
Prince Charles may not become King Charles III
Dickie also revealed that Prince Charles will inherit a plethora of impressive titles, including the Duke of Lancaster, Defender of the Faith, supreme Governor of the Church of England, Head of the Commonwealth, and King of other Realms and Territories. He added: "[Charles will] also be Lord of the Mann (Isle of Man) and Duke of Normandy. But generally he'll only be known as King."
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The royal family titles are steeped in tradition and have their own particular set of rules. For instance, despite a common misconception that Princess Charlotte will automatically become the Princess Royal when her father, Prince William, becomes King, just like her great-aunt, Princess Anne, this isn't necessarily the case.
The Queen with her two eldest children, Charles and Anne
In fact, the Queen's eldest daughter only accepted the title in 1987 when she was 36 years old. Speaking about her decision to accept it, royal historian Marlene Koenig told HELLO!: "There is a lot to be said for the timing. The Phillips marriage was already in trouble. They separated two years later, but in 1985, Mark became a father of Felicity Tonkin, born in New Zealand.
"This story broke in 1991, but there is no doubt that Anne already knew as Heather Tonkin had called Gatcombe to tell Mark that she was pregnant. Accepting the title of Princess Royal allowed Anne to stop being styled as HRH The Princess Anne, Mrs. Mark Phillips."
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