Cologne served as a base for the Carolingian conversion of the Saxons and Frisians. In 795 the chaplain to Charlemagne, Hildebold, was elevated to the newly created archbishopric of Cologne. After the death of Charlemagne, Cologne became part of Middle Francia. Archbishop Gunther was excommunicated in 863 for his support of the divorce and remarriage of Lothair II. In 873 Gunther's successor Wilbert consecrated what would become known as the "Alter Dom" (old cathedral), the predecessor of Cologne Cathedral. With the death of Lothair in 876, Cologne fell to East Francia under Louis the German. The city was burnt down by Vikings in the winter of 881/2.