Princess Diana and Prince Charles Wedding Day
Credit: Princess Diana Archive/Getty Images

Princess Diana was always a woman well ahead of her time. From her fashion to her charitable work, and her progressive views on the world, Diana was the best kind of trendsetter. And it appears she even started a royal wedding trend that's still in use today.

As Reader's Digest noted, the Anglican Book of Common Prayer has been used in royal weddings since 1662. In it a line reads, "to love, cherish, and to obey, till death us do part."

However, Diana was apparently vehemently opposed to using the word "obey" in her vows with Prince Charles during their wedding in 1981. After a bit of back and forth, she and Charles agreed to leave it out of their big day.

The news caused quite a stir, however, Dr. Edward Carpenter, the Dean of Westminster Abbey, had the couple's back. Just prior to their wedding he told The New York Times, ''Marriage is the kind of relationship where there should be two equal partners, and if there is going to be a dominant partner, it won't be settled by this oath. I think this is much more Christian.''

Their decision to leave out the word apparently inspired future royal women to follow suit.

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In 2011, for her wedding to Prince William, Kate Middleton also omitted the word from her vows.

"It's relatively rare for people to make a vow of obedience these days," Rev. Rod Thomas told The Telegraph at the time. "[Will and Kate's] marriage will be just as valid as that of anyone who does take a vow of obedience."

Meghan Markle left the word out of her vows when she married Prince Harry in May. And just last week, Princess Eugenie and her husband Jack Brooksbank vowed to "love, comfort, honor, protect, and be faithful to the other," and vowed to "have, to hold, to love, and to cherish." She too left "obey" out of her vows, despite the fact that her mother, Sarah Ferguson, Duchess of York, said the word in her wedding to Prince Andrew.

But, for now, it appears Diana's influence is here to stay and women promising to obey a man — king or otherwise — is simply out of fashion.