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Bonizo of Sutri


Bishop, canonist, and publicist under Gregory VII (known also as Bonitho, Bonitus); b. perhaps in Cremona, Italy, c. 1045; d. probably before 1095, but possibly as late as 1099. A native Lombard, Bonizo devoted his life to the reform of the Church in north Italy and to the gregorian reform in general, a program for which he was an extreme and uncompromising advocate. As a subdeacon leading the patarines in Piacenza, he came to the attention of Pope gregory vii, who made him bishop of the strategic See of Sutri (1075 or 1076) and employed him as legate (1078).

During the investiture struggle he was captured by Emperor henry iv (1082), but he escaped and took refuge with matilda of tuscany. While there, he wrote his most famous work, the Liber ad amicum [Monumenta Germaniae Historica (Berlin 1826) Libelli de lite, 1:568620], designed to rally all reformers after Gregory's death in 1085. Partisan, polemical, and panegyric, it is a personal and unreliable memoir of Gregory, although its distortions do not seem to be deliberate.

Around 1086 Bonizo was elected bishop of Piacenza, but the citizens expelled him from the city (1089), whereupon he resigned and devoted his last years to the Liber de vita christiana [ed. E. Perels (Berlin 1930)], a compilation of canonistic extracts with commentary. The exact date of his death is unknown.

Bibliography: p. fournier and g. lebras, Histoire des collections canoniques en occident depuis les fausses décrétales jusqu'au Décret de Gratien (Paris 193132) 2:139150. l. jadin, Dictionnaire d'histoire et de géographie ecclésiastiques (Paris 1912) 9:994998. e. nasalli rocca di corneliano, "Osservazioni su Bonizione vescovo di Sutri et di Piacenza come canonista," Studi gregoriani 2 (1947) 151162.

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