The royal baby finally has a name! After waiting four days after the birth of their third child, the Duke and Duchess of Cambridge formally announced through the Kensington Palace Twitter account on Friday, April 27 that they named their newborn prince Louis Arthur Charles.

Up until the big announcement, the name Arthur had been the favorite choice among people placing bets in the UK to be the prince's first name. Even though the first name Louis caught many by surprise today, the prince's two middle names are traditional choices that go back generations in the royal family.

The name Arthur has legendary connections to King Arthur, of course, but is also a family name for the Cambridges tied to very real people. Meaning "bear" in Celtic, Arthur is not only one of Prince William's middle names, but also is one of Prince Charles's too.

But the name Arthur goes even farther back in the royal family. The full name of King George VI (the Queen's father) was Albert Frederick Arthur George and Queen Victoria even named her seventh child Prince Arthur, who eventually would became the Duke of Connaught and Strathearn.

Prince Louis shares a middle name with both his father, Prince William, and his grandad, Prince Charles.

Charles, of course, is the first name of Prince Louis's grandfather, the Prince of Wales. It also appears in beloved uncle Prince Harry's full name, Henry Charles Albert David. The moniker also happens to be one of the middle names of Queen Victoria's beloved husband, Prince Albert, whose full name was Francis Albert Augustus Charles Emmanuel. Between those two family ties and the fact that two of England's monarchs have also been named King Charles in the past, it's a classic choice for the new prince.

Lyndsey Matthews is the Destination News Editor for AFAR; previously she was a Lifestyle Editor across all of Hearst Digital Media's brands, and a digital editor at Martha Stewart Weddings and Travel + Leisure.