Royal brides including Princess Kate, Princess Beatrice and Princess Diana all followed a special rule when choosing their bridal gowns.
When we first caught sight of the Princess of Wales and Princess Beatrice's wedding dresses, we were too absorbed in taking in all the details to consider the strict rules they had to follow.
That's right, royal brides can't just pick any silhouette from any designer, there has to be a lot of thought put into their choices. Aside from the fact that they are expected to sport modest and elegant gowns – which means short hemlines and low necklines are a no-go – they are also expected to pay their respects to the British monarchy by wearing a gown from a British designer. See all of their gorgeous choices in the video below...
WATCH: Most stunning royal wedding dresses over the years
Who designed Princess Diana's royal wedding dresses?
Looking back, this has been obeyed by everyone from Princess Diana to Meghan Markle. David and Elizabeth Emanuel designed Diana's iconic puff-sleeve wedding dress when she married King Charles in 1981.
"We did research that the longest royal train was 20ft, we said to Diana, 'What do you think? Let’s do 23ft,' and she blushed. And I said, 'Do you know what, let’s make it 25ft'," David told HELLO!. "Because St Paul's is vast, you couldn’t have a quiet unassuming dress. It had to make a statement," he added.
David and Elizabeth Emanuel designed Diana's iconic wedding dress
Sarah Burton for Alexander McQueen was behind Princess Kate's stunning lace gown, while Peter Pilotto and Christopher de Vos were responsible for Princess Eugenie's dress and Princess Beatrice opted to borrow her grandmother Queen Elizabeth's Norman Hartnell embellished frock.
FIND OUT: Will Lady Amelia Spencer wear Princess Diana's famous wedding tiara?
Eugenie chose Peter Pilotto and Christopher de Vos for her first gown, followed by Zac Posen for her second dress
Who designed Meghan Markle's royal wedding dress?
Considering her American heritage, and the fact she often sports US and Canadian designers, Meghan Markle surprised royal fans when she stepped out in a bateau neck dress by British stylist and designer Clare Waight Keller for Parisian fashion house Givenchy.
The Duchess of Sussex stepped out in a gown designed by Clare Waight Keller
Opening up about the design process for the gown, which reportedly took 3,900 hours to make, Clare wrote: "Purity and simplicity were the guiding principles, a narrative of nature through the 53 florals of the Commonwealth to bring the world into the journey of the ceremony and subtlety bringing the lines of Givenchy and the history of the Maison to capture the classical timeless beauty I knew she wanted to achieve."
Were there rules for royal brides' second wedding dresses?
This isn't to say that royal brides didn't push the boundaries a little with their second wedding dresses – Princess Eugenie chose an unconventional blush pink gown by American designer Zac Posen, while the Duchess of Sussex had her shoulders on display with her Stella McCartney halterneck gown.
Check out more rebellious royal wedding dresses here.
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