Labels:dialog box | sky | web site OCR: Post Boman Pre Gregorian 400 600) Celtic Gregorian (600 800) Carolinoian ottonian 800 1000) Romanesque Norman 1000 11501 Early Gothic Ars Antiqua (1150-1300) Late Gothic Ars Nova (1300 (4400 Roman Carolingian Romanesgue Antioua