“Another black-and-white photo, which features the Duchess of Cambridge in profile, reflects the ethereal, regal quality of the renowned court photographer Cecil Beaton, who captured historic images of Princess Margaret and the Queen Mother, and searches for ‘Cecil Beaton’ also exploded 669 percent one day after the photos were released.

“All three photographs already have the feel and weight of history, and will remain iconic images of the monarchy as the centuries progress.”

The fascination with Kate’s latest outfit is nothing new, as the Duchess’ style choices frequently cause a fashion frenzy among royal watchers.

The desire to emulate Kate’s style has long been coined the ‘Kate effect’ by commentators and the media – here’s why.