In 1956, when Kelly made the transition from Hollywood film star to real-life princess, her Sac à Dépêches became a part of the story too. A few months after her marriage to Prince Rainier III of Monaco, she stepped out in a typically elegant ensemble: a full-skirted dress, wrist-length gloves, fur coat slung over her shoulders … and her Sac à Dépêches carried prominently in front of her.

The bag was sophisticated enough to suit the outfit – and supposedly large enough to hide the growing baby bump she wasn’t yet ready to announce.

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Countless variations have been released by Hermès across the years, with renderings in everything from ostrich to wicker to wood, and style variations from briefcases to backpacks. Through it all, the distinctive elements of the Kelly – its trapezoid shape, triangular gussets, cut-out front flap, and turn-lock closure in either gold-plated or palladium-plated hardware – have remained the same.

Regardless of the incarnation, the Kelly is more than a bag: it’s a status symbol, an heirloom, an investment piece that only ever grows in value. We can thank the bag’s timeless aesthetics and glamorous history for that, but also its unparalleled quality – each one is crafted by a single artisan, who spends around 20 hours stitching together 36 separate pieces of leather using 680 hand stitches.

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In 1977, the Sac à Dépêches was finally renamed by Hermès as the Kelly bag in recognition of its illustrious association and an acknowledgement that this is, indeed, a bag fit for a princess.