Middle Ages Egypt and suffering from a series of internal civil wars. The Byzantines also faced a revived Bulgaria, which in the late 12th and 13th centuries spread throughout the Balkans. The crusades were intended to seize Jerusalem from Muslim control. The First Crusade was proclaimed by Pope Urban II (pope 1088–99) at the Council of Clermont in 1095 in response to a request from the Byzantine Emperor Alexios I Komnenos (r. 1081–1118) for aid against further Muslim advances. Urban promised indulgence to anyone who took part. Tens of thousands of people from all levels of society mobilised across Europe and captured
Pope Urban II Ravenna who held Rome as the antipope "Clement III". Gregory had repeatedly clashed with the emperor Henry IV over papal authority. Despite the Walk to Canossa, Gregory had backed the rebel Duke of Swabia and again excommunicated the emperor. Henry finally took Rome in 1084 and installed Clement III in his place. Urban took up the policies of Pope Gregory VII and, while pursuing them with determination, showed greater flexibility and diplomatic finesse. Usually kept away from Rome, Urban toured northern Italy and France. A series of well-attended synods held in Rome, Amalfi, Benevento, and Troia supported him in renewed