(20 Jan.–10 Mar. 1045: d. 1063)
When Benedict IX was violently ejected from Rome in Sept. 1044, the Romans, after bitter and protracted infighting, elected and installed Bishop John of Sabina (the homeland of the Crescentian family) in Jan. 1045. The Crescentians were behind the move; they were using him, probably as a reluctant instrument, to win back the supreme power the Tusculans had wrested from them in 1012. He was later charged, probably libellously, with having used bribery to get himself elected. He adopted the name Silvester, but on hearing of his appointment Benedict promptly sought to undermine any legitimacy he might have by excommunicating him. His reign was short, for on 10 Mar. Benedict staged a comeback and expelled him with ignominy. He returned to his original see, which he had not relinquished; here the protection of the Crescentians enabled him to ignore the papal ban and carry on with his episcopal duties. Some eighteen months later, when King Henry III of Germany (1039–56) intervened, he was cited before the synod of Sutri (20 Dec. 1046), condemned as an invader of the holy see, and sentenced to confinement in a monastery and deprivation of orders. The sentence must have been suspended, however, for he continued to function, and to be recognized, as bishop of Sabina until at least 1062; he must have died before Oct. 1063, when the name of a successor is recorded. Succeeding popes probably left him undisturbed because he was known to have no ambition for the papal throne. His right to be considered an authentic pope is open to question. He was among those who signed the decree of 1059 on papal elections.
JW i. 523 f., 525Watterich i. 70, 72–6, 713–15DTC xiv. 2083 f. (É. Amann)Seppelt ii. 414–17Z1: 121–34EThC 134 (E.-D. Hehl)Levillain iii. 1422–3 (K.-J. Herrmann)J. Gay, Les Papes du XIe siècle et la chrétienté (Paris, 1926)