Princess Diana attends a preview of her 'Dresses Auction' at Christies in London (UK Press via Getty Images) After making such a profound impact on the royal fashion scene, it's hard to remember a time when the late Princess of Wales wasn't an international celebrity. Princess Diana, nee Diana Spencer, was pictured taking on bridesmaid duties at her older sister Lady Jane's wedding in 1978, two years before she began dating King Charles.