Princess Elisabeth Charlotte (; known as Liselotte von der Pfalz, 27 May 1652 – 8 December 1722) was a German princess member of the House of Wittelsbach and, as "Madame" ("Duchesse d'Orléans"), the second wife of Philippe I, Duke of Orléans (younger brother of Louis XIV of France), and mother of Philippe II, Duke of Orléans, France's ruler during the Regency. She gained literary and historical importance primarily through her correspondence, which is of cultural and historical value due to her sometimes very blunt descriptions of French court life and is today one of the best-known German-language texts of the Baroque period.