Once Princess Diana married Prince Charles in 1981, people immediately began calling her a princess. But this same rule has not applied to her son Prince William's wife.
When Kate Middleton married Prince William and became Her Royal Highness Catherine, Duchess of Cambridge, fans seemed disappointed that she hadn't been given the title of Princess.
While it is a convoluted explanation, there is a logical reason why she should not be called Princess Catherine. As with anything related to the British Royal family, it is all about tradition.
Even though pretty much nobody uses the title, Catherine is considered a princess. Her official (and long) title is Her Royal Highness Princess William, Duchess of Cambridge, Countess of Strathearn, Baroness Carrickfergus.
In an archaic rule, women take their husband's name when they marry, so she can only be called a Princess if referred to as "Princess William."
In British Royalty, one person may be awarded many different titles, depending on their rank. To avoid the confusion of calling them by their full titles, most royals choose one major title out of their list by which they are generally known.
BECOMING A PRINCESS
One of Prince William's titles is Duke of Cambridge. A dukedom is not necessarily a lower title than a princehood, and William is more often referred to as the Duke of Cambridge since he got the title on his wedding day.
When Prince Charles ascends to the throne, Kate's title may once again change as her husband becomes the new Prince of Wales.
As such, his wife uses her corresponding title, which is that of the Duchess of Cambridge. The reason why Diana got the Princess title and was called that way was that her husband received the title of Prince of Wales, and this is to this day his major title. Therefore his wife became the Princess of Wales.
However, Kate was officially acknowledged as a princess in the birth certificates of her kids, specifically under her occupation. Meanwhile, "blood princesses" or those born into royalty can keep the titles as part of their names.
The rule applies to Prince Andrew's two girls, Princess Beatrice and Princess Eugenie. Even when the two women got married, they decided to keep their titles.
Similarly, Kate and William's daughter, Princess Charlotte, was born with the title and can use it as she pleases. The same goes if the couple has another daughter.
Prince William, Kate Middleton with their children at a special pantomime performance at London's Palladium Theatre, hosted by The National Lottery on December 11, 2020 | Photo: Getty Images
Catherine has certainly emulated her late mother-in-law in many ways, showing her same modesty and charitable nature, as well as displaying a similar wardrobe on many occasions and wearing Diana's engagement ring.
William has also spoken of his sadness that his mother never got to meet his wife, and that she will never see his three children grow up. Diana, unlike Kate, was referred to as Princess although not born into royalty.
Princess Diana at St. Columb Major in Cornwall, England, on May 1983 | Photo: Getty Images
"The British royal family follows the older German style of royal wives, by styling the wife by her husband's name. The Press called her Princess Diana [...]."
Diana Princess of Wales and Prince Charles during the Royal Tour of Canada in 1983 | Source: Getty Images
Today, Kate goes by the name Catherine more often as she entered the royal family. According to Adam Helliker, a royal expert, the dutchess asked her friends to start calling her Catherine when she got together with William.
Catherine seemed like a more formal name to use and suit her new title. However, when Prince Charles ascends to the throne, Kate's title may once again change as her husband becomes the new Prince of Wales.
She will likely become Princess of Wales, the same title Diana held, which Charles' second wife, Camilla, refused to use out of respect for the late Princess.