Princess Eugenie, granddaughter of George I, King of the Hellenes (1910–1989)

Princess Eugénie was the daughter of Prince George of Greece and Denmark and his wife, the French psychoanalyst Princess Marie Bonaparte. Her paternal grandfather was King George I of Greece, and she was descended on her mother's side from the Emperor Napoleon's brother Lucien. In 1938, she married Dominik Rainer Radziwiłł, with whom she had two children before divorcing in 1946. She married as her second husband Prince Raymundo della Torre e Tasso, Duke of Castel Duino, and is usually known as Duchess of Castel Duino. She wrote Le Tsarevitch, Enfant Martyr, a biography of the son of Tsar Nicholas II, published in 1990.