Nicholas, also known as Nicholas the Great, is one of three popes to be honored with the appellation "the Great" (the others are St. Leo I [r. 440-461] and St. Gregory I [r. 590-604]). A tireless defender of Christian morality, he insisted upon the supremacy of the Church over the state. His personal life was guided by a spirit of earnest Christian asceticism and profound piety.
Nicholas was born between 819 and 822 to Roman Defensor Theodore. He joined the priesthood of the Roman Church in his youth, was made subdeacon by Pope Sergius II (r. 844-847) and deacon by Pope St. Leo IV (r. 847-855). He was a trusted adviser of Pope Benedict III (r. 855-858).
At Benedict's death on April 7, 858, the Prankish emperor Louis II, who was then near Rome, came into the city, hoping to influence the election of a successor. On April 22, Nicholas was elected and enthroned in St. Peter's basilica, with the emperor in the audience.
Nicholas's elevation came at a time of turmoil in Western Europe, both within and without the Church. Charlemagne's Holy Roman Empire lay in ruins, and Christian lands were threatened from both the north and east. Ecclesiastical discipline, meanwhile, had largely broken down. Nicholas issued letters and decisions against bishops who were negligent in their duties. He was especially active in regard to the Church's marriage laws. When the wife of Count Boso left her husband for a lover, Nicholas commanded her bishops to excommunicate her unless she returned to her husband. When the woman ignored the summons to appear before the Synod of Milan in 860, the sentence was carried out. Nicholas also forced Charles the Bald to accept the marriage of his daughter Judith to Baldwin of Flanders, made without his consent, and compelled the Prankish bishops to withdraw the excommunication they had imposed on her.
Nicholas ran into trouble, however, when he opposed King Lothair II of Lorraine, who had left his wife Theutberga for another woman. In April 862, the bishops of Lorraine at the Synod of Aachen approved of the new union. Then in June 863, at the Synod of Metz, papal legates were bribed by Lothair to assent to the Aachen decision. This was enough for Nicholas, who brought the matter before his own council at the Lateran Palace that October. He condemned Lothair's new marriage and deposed two of the bishops who had approved it. Lothair then advanced on Rome with his army and held the city under siege, so that the pope was confined in St. Peter's for two days without food. Nicholas and Lothair eventually reconciled, and Lothair withdrew; although Nicholas never ceased trying to bring about a reconciliation between Lothair and Theutberga, he never succeeded.
Nicholas not only endeavored to enforce the Church's teachings, he sought to spread them through missionary work as well. He sent St. Anskar as a missionary to Scandinavia and when, in August 863, Prince Boris of Bulgaria—who had been converted to Christianity by Greek missionaries—sent him a delegation carrying 106 questions on the teaching and discipline of the Roman Church, Nicholas took the time to answer them exhaustively in a now-celebrated document, the "Responsa Nicolai ad consulta Bulgarorum." His return delegation was instructed to do what they could to win over Boris. Nevertheless, in the end he joined the Eastern Church.
This could not have pleased Nicholas, since he was also involved throughout his pontificate in a controversy with the Greek emperor Michael III over his illegal deposition of Patriarch Ignatius of Constantinople and the appointment of Photius in his place. In 863, Nicholas excommunicated Michael, and Photius ex-communicated Nicholas. The matter was resolved only when the newly crowned emperor Basil I expelled Photius on November 13, 867, the day Nicholas died.
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