Pope from 858. His pontificate witnessed a protracted struggle with the E. Church. He refused to sanction the Emperor's deposition of Ignatius and appointment of Photius to the see of Constantinople, and in 863 he pronounced Ignatius restored. He also tried to win over the newly converted Bulgars to Rome. In 867 Photius declared the Pope deposed, but was himself deprived of office later in the year. In the W. Nicholas took a firm stand in the divorce case of Lothair II of Lorraine; he asserted the supremacy of the see of Rome over Abp. John of Ravenna, and he forced Hincmar of Reims to accept the right of the Papacy to intervene in disputes. Feast day, 13 Nov.