In fairy tales, a princess wears a tiara, a ball gown, and crystal glass slippers. But what happens when princesses step out of that royal mold and into a pair of jeans?

I’ve spent nearly a decade studying royal wardrobes, from Queen Elizabeth II’s coronation robe to Kate Middleton’s first engagements as a duchess to Archie’s H&M overalls. I’m the editor of What Would Kate Do? and Meghan’s Mirror, which means I’ve analyzed thousands of outfits throughout my career. There are a few things I’ve learned: Royals think about every element of what they wear, there are rarely any mistakes or coincidences, and every outfit is meant to send a message. When a member of a royal family steps out in something as accessible as jeans, they’re consciously saying something to the public. We may see a casual outfit, but there may be a larger message, or historic moment, being represented in their denim.

These game-changing moments have represented everything from women’s empowerment to shaping their public image, to supporting environmentally conscious fashion, to ultimately changing the monarchy. And they predate Meghan Markle.

Ahead, we round up the most memorable denim looks that have shifted the way we think about royal fashion.

Christine Ross is the creative director at Effervescence Media and the editor of What Would Kate Do? and Meghan’s Mirror.