José Luis de Vilallonga y Cabeza de Vaca, IX marquis de Castellbell (Madrid, 1920 - Andratx, Mallorca, 2007) was an aristocrat, writer and Spanish actor. He rejected the diplomatic career that his family wanted him to follow and thanks to his contacts, had the opportunity to make friends with many celebrities of the political and artistic world. He participated in over 70 films including Lovers of Louis Malle and Breakfast with Diamonds (Breakfast at Tiffany's, 1961). He published Allegro barbaro in 1978 and La nostalgia es un error in 1980. He was spokesman of the Democratic Board during the Transition and wrote an authoritative biography of Juan Carlos I, El Rey. Perhaps his best work is the four volume autobiography, Unauthorized Memoirs.