MARIANO VITTORI. — Bishop, born in Rieti in 1518, died there on 29 June 1572. After completing his studies in Siena, he was ordained a priest and then moved to Rome, where, having learned Greek, he published the first *Institutiones grammaticales* (Rome 1552).
The following year he accompanied Cardinal Reginald Pole, sent by Pope Julius III to England in an attempt to heal the religious schism. Cardinal Giovanni Morone, whom V. had accompanied to the sessions of the Council of Trent, encouraged him to write the treatise *De Sacramento confessionis*, aimed at refuting Protestant assertions. He also composed the four-book work *De antiquitatibus Reatis*, notable, especially Book IV, for its topography and history of the Sabine region. Finally, he carefully edited and corrected, with keen insight and learning, the works of St. Jerome, in contrast to the edition produced with reformist tendencies by Erasmus of Rotterdam, earning unanimous praise, including that of Cardinal Baronio (*Martyrologium Romanum*, Rome 1630, p. 485). He also served on the commission of theologians and ecclesiastics tasked with revising the Decree of Gratian. St. Pius V sought V. as his secretary, but he managed to avoid the high office out of humility and love for his studies (v. ’s own autograph letter to Canon Cappelletti, 15 Aug. 1572). Nonetheless, in recognition of his merits, the same Pontiff appointed him Bishop of Amelia and later transferred him to the See of Rieti.