Nicholas refused King Lothair II of Lotharingia's request for an annulment of his marriage to Teutberga. When a council pronounced in favor of annulment, Nicholas I declared the council deposed, its messengers excommunicated, and its decisions invalid. Despite pressure from the Carolingians, who laid siege to Rome, his decision held. During his reign, relations with the Byzantine Empire soured because of his support for Patriarch Ignatios of Constantinople, who had been removed from his post in favor of Photius I.
nicholas refused king lothair ii of lotharingia's request for an annulment of his marriage to teutberga when a council pronounced in favor of annulment nicholas i declared the council deposed its messengers excommunicated and its decisions invalid despite pressure from the carolingians who laid siege to rome his decision held during his reign relations with the byzantine empire soured because of his support for patriarch ignatios of constantinople who had been removed from his post in favor of photius i