Everyone remembers Grace Kelly and Prince Rainier in 1956 as the moment Hollywood moved into a palace. Seven years earlier it had already happened, only with a different bride. On 27 May 1949 Rita Hayworth married Prince Aly Khan at the Chateau de l'Horizon on the French Riviera, and what she wore that day is still more interesting than everything that came after.

The dress was not white. It was sky-blue silk muslin by Jacques Fath, with a V-neck bodice and a pleated skirt to mid-calf. It came with a wide-brimmed hat in the same tone, a bouquet of orange blossom, black shoes and black gloves. In 1949 that was not an aesthetic choice - it was a public statement.

The rest of the wedding was everything the era could offer. Over 500 guests - princes, princesses and aristocrats from around the world. Over 600 bottles of champagne. Twenty kilos of caviar. And 450 litres of cologne poured into the hotel pool, on whose surface the couple's initials were laid out in fresh flowers. A special carpet was rolled out for the bride.

The story began a year earlier, in 1948. Hayworth, already famous for her role in "Gilda", met the prince on a yacht on the French Riviera while her marriage to Orson Welles was falling apart. He was a playboy and an admirer, and he bombarded her with flowers, jewellery and invitations to private parties.

What she said mattered to her was not the luxury. She already had that. What the prince was offering her was a way out of fame - a place where she would not be "Gilda". That is a request no amount of caviar can fulfil, and it showed quickly.

The marriage produced a daughter, Yasmin Aga Khan. In 1953, four years after the wedding with 500 guests, came the divorce - infidelities and disappointments. The wedding of the century lasted forty-eight months.

Still, that blue dress outlived the whole story. Bianca Jagger is usually regarded as the one who broke the white-bride tradition. Rita Hayworth did it twenty-two years earlier, at the most-watched wedding of her decade, and nobody credits her for it.