VICTOR III. (Dauferius Epifani), pope from the 24th of May 1086 to the 16th of September 1087, was the successor of Gregory VII. He was a son of Landolfo V., prince of Benevento, and was born in 1027. After studying in various monasteries he became provost of St Benedict at Capua, and in 1055 obtained permission from Victor II. to enter the cloister at Monte Cassino, changing his name to Desiderius. He succeeded Stephen IX. as abbot in 1057, and his rule marks the golden age of that celebrated monastery; he promoted literary activity, and established an important school of mosaic. Desiderius was created cardinal priest of Sta Cecilia by Nicholas II. in 1059, and as papal vicar in south Italy conducted frequent negotiations between the Normans and the pope. Among the four men suggested by Gregory VII. on his death-bed as most worthy to succeed him was Desiderius, who was favoured by the cardinals because of his great learning, his connexion with the Normans and his diplomatic ability. The abbot, however, declined the papal crown, and the year 1085 passed without an election. The cardinals at length proclaimed him pope against his will on the 24th of May 1086, but he was driven from Rome by imperialists before his consecration was complete, and, laying aside the papal insignia at Terracina, he retired to his beloved monastery. As vicar of the Holy See he convened a synod at Capua on the 7th of March 1087, resumed the papal insignia on the 21st of March, and received tardy consecration at Rome on the 9th of May. Owing to the presence of the antipope, Clement III. (Guibert of Ravenna), who had powerful partisans, his stay at Rome was brief. He sent an army to Tunis, which defeated the Saracens and compelled the sultan to pay tribute to the papal see. In August 1087 he held a synod at Benevento, which renewed the excommunication of Guibert; banned Archbishop Hugo of Lyons and Abbot Richard of Marseilles as schismatics; and confirmed the prohibition of lay investiture. Falling ill at the synod, Vicar returned to Monte Cassino, where he died on the 16th of September 1087. He was buried at the monastery and is accounted a saint by the Benedictine order. His successor was Urban II.
Victor III., while abbot of Monte Cassino contributed personally to the literary activity of the monastery. He wrote Dialogi de miraculis S. Benedicti, which, along with his Epistolae, are in J. P. Migne, Patrol. Lai. vol. 149, and an account of the miracles of Leo IX. (in Ada Sanctorum, igth of April). The chief sources for his life are the " Chronica monasterii Casinensis," in the Hon. Germ. hist. Script, vii., and the Vitae in J. P. Migne, Patrol. Lai. vol. 149, and in J. M. Watterich, Pontif. Roman. Vitae.
See J. Langen, Geschichte der romischen Kirche von Gregor VII. bis Innocenz III. (Bonn, 1893); F. Gregorovius, Rome in the Middle Ages, vol. 4, trans, by Mrs G. W. Hamilton (London, 1900-2); K. J. von Hefele, Conciliengeschichte (2nd ed., 1873-90), vol. 5; Hirsch, " Desiderius von Monte Cassino als Papst Victor III.," in Forschungen zur deutschen Geschichte, vol. 7 (Gottingen, 1867); H. H. Milman, History of Latin Christianity, vol. 3 (repub. London, 1899).
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)