Officially Violet's father was Hon George Keppel, a son of the 7th Earl of Albemarle, but it is thought that her real father was William Beckett, subsequently 2nd Baron Grimthorpe, a banker and MP for Whitby. Violet's mother, Alice Keppel, was the mistress of the Prince of Wales, subsequently King Edward VII, from 1898 until the King's death in 1910.
Violet met Vita Sackville-West at a party when she was 10. They became close friends and spent time together in Italy. In 1913 Vita married Harold Nicolson, but Vita and Violet soon became lovers, causing a scandal. Under pressure from her mother, Violet married Denys Trefusis, but the marriage was not a success. Vita and Violet resumed their relationship, but Harold persuaded Vita to return to the family home. Violet moved to Paris where she become the lover of Princesse Edmond de Polignac (formerly Winnaretta Singer), daughter of the inventor of the sewing machine and heir to a massive fortune.
Violet wrote novels and non-fiction works, in both English and French. Both she and Vita wrote novels based on their affair, but in a heterosexual guise. Violet was also the basis for fictional characters including "Sasha" in Virginia Woolf's Orlando: A Biography, "Lady Montdore" in Nancy Mitford's Love in a Cold Climate, and "Muriel" in Harold Acton's The Soul's Gymnasium.
- http://www.oxforddnb.com/view/article/76253Clare L Taylor, "Trefusis, Violet (1894–1972)" Oxford Dictionary of National Biography, Oxford University Press 2004