Charles IV (; ; ; 14 May 1316 (Jul. calendar) / 22 May 1316 (Greg. calendar) – 29 November 1378), born Wenceslaus (), was the first King of Bohemia to become Holy Roman Emperor. He was a member of the House of Luxembourg from his father's side and the Czech House of Přemyslid from his mother's side; he emphasized the latter due to his lifelong affinity for the Czech side of his inheritance, and also because his direct ancestors in the Přemyslid line included two saints.