Donna Maria Beatrice Olga Alberta Caracciolo was the daughter of the Neapolitan nobleman Gennaro Caracciolo Pinelli, Duke Caracciolo (b. 1849), and his wife, the former Marie Blanche Sampayo (1849–1890). Her godfather was Albert Edward, the Prince of Wales and later King Edward VII. She married the nobleman Marino Brancaccio (1852-1920) in 1892 and they divorced in 1899. She then married the photographer Adolph de Meyer (1868–1946) - the marriage is recorded on 25 July 1899 between Maria Beatrice Olga Brancaccio, Princess de Moavero, and Baron Adolphus Edward Sigismond von Meyer.
She met Whistler in Dieppe, where she lived for many years. She may have posed to Whistler for Arrangement in Pink, Red and Purple y324. She also posed to Jacques Émile Blanche (1861-1942), John Singer Sargent (1856-1925), Paul-César-François Helleu (1859-1927) and others.
https://en.wikipedia.org/wiki/Olga_de_Meyer