The members of the British royal family, who are more popularly known by their first names, have a surname too.

According to Express, the royal family traditionally did not have a surname. However, in 1917, King George V decreed that the family would use the surname Windsor. The royal family previously had Saxe-Coburg-Gotha as their house name. However, King George found it to be too Germanic. Since there was an anti-German feeling at the time, he decided to change it to Windsor, taken from the royal property Windsor Castle.

In 1960, Queen Elizabeth II and Prince Philip decided to pick another surname for their family. The royal couple decided to use Prince Philip's surname, Mountbatten, and hyphenated it with Queen Elizabeth II's Windsor. Thus, their descendants carry the family name Mountbatten-Windsor.

Although the royal family has a surname, they do not usually use this. On their official website, it stated that a "proclamation on the Royal Family name [...] does not pass into the law of the land." Thus, British royals do not necessarily need to use the official surname. In addition, the heirs are not required to use the last name set by their predecessors.

Royals with the title "His Royal Highness Prince" or "Her Royal Highness Princess" also don't need to use a surname. This explains why Prince Charles, Prince William and Prince Harry don't use any family name, except for special instances.

One such circumstance was when Prince William and Prince Harry served in the military, where both used Wales as their last name. This is in reference to their father, Prince Charles, who is the Prince of Wales. The same applies to the princesses.

For instance, Princess Eugenie and Princess Beatrice opted to use York because their father, Prince Andrew, is the Duke of York. Meanwhile, Prince Edward's daughter uses Windsor without Mountbatten.

In related news, Queen Elizabeth II disclosed in her coronation documentary that her crowns were so heavy that they could break a neck. In fact, when she read her speech, she had to bring it up.

"You can't lean down to read your speech. You have to bring [the speeches] up. Because if you did your neck would break and it would fall off," Queen Elizabeth II said. "Nothing like that is comfortable."

The monarch also made a surprising revelation when she confessed that 2-year-old Princess Charlotte bosses around her big brother, 4-year-old Prince George. The two royals will have a new sister or brother soon as Prince William and Kate Middleton are expecting their third baby in April.