Barbara of Cilli, Slovenian noblewoman
Barbara of Cilli or Barbara of Celje (Hungarian: Cillei Borbála, German: Barbara von Cilli, Slovenian and Croatian: Barbara Celjska, 1392 – 11 July 1451), was the Holy Roman Empress and Queen of Hungary and Bohemia by marriage to Holy Roman Emperor Sigismund. She was actively involved in politics and economy of her times, independently administering large feudal fiefdoms and taxes, and was instrumental in creating the famous royal Order of the Dragon. She served as the regent of Hungarian kingdom in the absence of her husband four times: in 1412, 1414, 1416, and 1418.