MAFFEI, GIAMPIETRO. — Jesuit, humanist, and historiographer, born at Bergamo in 1535, died at Tivoli (Rome) on 21 October 1603.
Already a professor of eloquence at Genoa and secretary of the Republic (1563–64), he entered the Society of Jesus in 1565, and as early as 1567–68 was teaching eloquence at the Collegio Romano. His version, in exquisite Latin, of the work of Fr. E. Acosta, Rerum a Societate Jesu in India gestarum (Dilinga 1571), with an appendix of missionaries’ letters, procured him an invitation to Lisbon from Cardinal Enrico of Portugal, so that, using the rich material gathered there, he might describe the Portuguese conquest and evangelization of India. There he in fact prepared (1572–81) the work Historiarum Iudicarum libri XVI (Florence 1588; classical Italian translation by F. Serdonati, 2 vols., Florence–Venice 1589). In the meantime he had published De vita et miraculis s. Ignatii (Rome 1585) and was preparing Le vite di XVII santi confessori (ibid. 1609). Entrusted with composing the life of Gregorio XIII, and having gathered extensive informational and documentary material (preserved in the Boncompagni Archive and described by Pastor, IX, pp. 816–922), he delivered it completed to the revisers in 1597. It was not, however, printed, but was tampered with, with considerable changes and alterations, by Paolo Teggia, secretary of the Boncompagni household. This deplorable reworking never saw the light of day; and M.’s work, based on the Barberini manuscripts, judged more authentic and free from interference, finally appeared under the editorship of C. Coquelines: Annali di Gregorio XIII (2 vols., Rome 1742). He was also entrusted with composing the life of Clemente XIII and gathered a great deal of material (preserved in the Borghese collection of the Vatican Archive [III, 129 B]); but he drafted only the first three books, which were published posthumously under a title not given by the author: Historiarum ab excessu Gregorii XIII libri tres, Sixti V pontificatum complexi (Bergamo 1746). This led people to believe that he had been commissioned to write the lives of Gregorio XIII’s successors, whereas the work describes the missions undertaken by Aldobrandini before his pontificate. These last two works still retain, even after subsequent research and study, the value of principal and indispensable sources.