As the world becomes more and more obsessed with Kate Middleton, Prince William and their adorable kids, fans still often ask one burning question about the British royal family — what is their last name?
Unfortunately, the answer to this common inquiry isn't so simple.
Though the royal family often goes without a surname altogether, any descendant of Queen Elizabeth II "other than those with the style of Royal Highness and the title of Prince/Princess, or female descendants who marry" has the last name Mountbatten-Windsor.
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The Windsor portion of the famous brood's surname comes from Queen Elizabeth's father, King George V. King George chose Windsor — which also distinguishes the monarch's royal house — as his family's last name in 1917 during World War I. Before that time, the royals had no official surname, but used the name of the house or dynasty to which they belonged.
Queen Elizabeth, Prince Philip and their four children in 2007. (Photo Credit: Getty Images)
The royal name Windsor was again confirmed by Queen Elizabeth when she ascended to the throne in 1952 — but with an interesting twist. The queen and her husband, Prince Philip, wanted their direct descendants to also carry on Philip's surname, Mountbatten, in an effort to distinguish them from the rest of the royal family.
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So, in 1960, the Privy Council declared that all the queen's children would use Mountbatten-Windsor for all occasions where a surname was required.
But, since William and his two kids, Prince George and Princess Charlotte — and many other members of the royal family! — all style their names with Prince/Princess, their last name is barely utilized.
Kate, William, George and Charlotte in 2016. (Photo Credit: Getty Images)
In this case — or when a royal uses "His/Her Royal Highness" to proceed their first name — Prince William and his younger brother, Prince Harry, sometimes non-formally go by William and Harry Wales, which refers to their father Prince Charles' title as the Prince of Wales.
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If that's not confusing enough, things got even more complicated when William and Kate welcomed their first child, son George, in July 2013. The couple could have chosen Mountbatten-Windsor as George's surname, but they also could have chosen Cambridge, because Kate and William's royal titles are the Duke and Duchess of Cambridge.
For those of you really eager to know, George's legal full name is George Alexander Louis Mountbatten-Windsor, though he most-often goes by His Royal Highness Prince George, Prince George of Cambridge or simply, Prince George. And, his little sister, Charlotte — who was born in May 2015 — has the Mountbatten-Windsor surname too.
Click through the gallery below to see more fascinating royal facts!
The royal went by the name as a child because she couldn't pronounce Elizabeth when she was a baby.