Pope Gregory IV

Gregory IV became bishop of Rome in October 827, inheriting a papacy caught in the gravitational pull of Carolingian politics. His seventeen-year reign was dominated by the bitter family struggle between Emperor Louis the Pious and his sons, a conflict Gregory attempted to mediate without success. In 843, a year before his death, the empire split apart in the Treaty of Verdun—the formal end of Charlemagne's unified realm. Gregory died on 25 January 844, having witnessed the dismantling of the political order that had defined his entire pontificate.