Princess Irene of Hesse and by Rhine (b. 1866)
Princess Irene Luise Marie Anne of Hesse and by Rhine (11 July 1866 – 11 November 1953) was the third child and third daughter of Princess Alice of the United Kingdom and Louis IV, Grand Duke of Hesse and by Rhine. Her maternal grandparents were Queen Victoria and Prince Albert of Saxe-Coburg and Gotha. Her paternal grandparents were Prince Charles of Hesse and by Rhine and Princess Elizabeth of Prussia. She was the wife of Prince Henry of Prussia, a younger brother of Wilhelm II, German Emperor and her first cousin. The SS Prinzessin Irene, a liner of the North German Lloyd was named after her.

Her siblings included Princess Victoria of Hesse and by Rhine, wife of Prince Louis of Battenberg, Grand Duchess Elizabeth Feodorovna of Russia, wife of Grand Duke Sergei Alexandrovich of Russia, Ernest Louis, Grand Duke of Hesse and by Rhine, and Empress Alexandra Feodorovna of Russia, wife of Tsar Nicholas II of Russia. Like her younger sister, the empress, Irene was a carrier of the hemophilia gene, and Irene would lose her sisters Alix and Elisabeth in Russia to the Bolsheviks.