This year’s Cannes festival is well and truly underway – but no one can steal the show in the way Princess Diana did when she attended in 1987.

While the people’s princess is most well-known for her dedicated humanitarian work, and of course, the legacy of her sons William and Harry, her fashion sense was also one of the most celebrated things about her. And the Princess constantly rose to the occasion. Whether it was a formal skirt/suit combo for a visit to a local hospital, or an elegant ballgown for dinner at the White House, she never looked anything less than flawless.

But perhaps one of her most famous looks ever was her flowing chiffon blue ballgown at the 1987 Cannes Film Festival, where she attended the filmic event with Prince Charles by her side. By this time, the couple had been married for over seven years and, as far as the public were aware, their relationship was going along swimmingly.

It was the early days of Diana’s history within the royal family, when she was referred to as “Shy Di”.  She was famed for her doe-eyed and demure look,  and her subtle, quiet appearance at events. But despite her shyness, the Princess was already clearly smart in her fashion choices.

So why did Diana choose this look, for an event where she knew the whole world would be watching?

This ethereal, otherworldly gown suits her new role as Britain’s new “fairy-tale Princess” perfectly. It’s easy to see why, in those days, Diana was regularly compared to the other, world-famous Princess, Grace Kelly – or Princess Grace. Both princesses were renowned for their beauty and their fairy-tale fashion choices, and both were equally the sweetheart of their respective nations. Princess Grace also made a striking debut at Cannes Festival, back in 1995. So perhaps Diana was keen to replicate the success!

Diana’s Cannes dress was designed by Diana’s favourite designer Catherine Walker, who helped to co-ordinate most of Diana’s outfits, for anything from visits abroad to red carpet appearances. The elegant and delicate number only cemented her position as the world’s adored sweetheart. And the images captured Diana as nothing less than the people’s princess.

The gown was of course by a famed British designer, which proved that early on Diana knew the importance of supporting British designers at popular events abroad. This is also an understanding that has carried all the way through to the Duchess of Cambridge, who regularly champions British designers such as Amanda Wakeley when off on royal visits abroad.