Emilie of Hesse-Kassel (11 February 1626 â 15 February 1693), was a German princess of the House of Hesse-Kassel and by marriage, in 1648, Duchess of Thouars. She was the sister of Charlotte of Hesse-Kassel, Electress Palatine and aunt of The Duchess of Orléans who she was with at the French court.