MAFFI, PIETRO. — Cardinal, archbishop of Pisa, born at Corteolona (Pavia) on 12 October 1858, died at Pisa on 17 March 1931. He completed his studies at the Seminary of Pavia, where, immediately after being ordained a priest (1881), he taught philosophy, while also devoting himself successfully to the physical sciences, especially astronomy, geodynamics, and meteorology. Several publications bear witness to this; notable among them are Nei cieli. Pagine di astronomia popolare (Como 1898; 5th ed., Turin 1928) and the Rivista di scienze fisiche e matematiche (1900–1912), which he founded and which was immediately received with great favor.
He combined study with a fruitful pastoral life; as vicar general, he followed his bishop, Mons. Riboldi, to Ravenna after the latter was appointed cardinal (1901); in 1902 he was consecrated bishop and appointed auxiliary to the new archbishop, Mons. Conforti; in 1903 he was promoted archbishop of Pisa; in 1904 he was appointed director of the Vatican Observatory, which he helped transform into one of the finest and best-equipped in Europe, and was entrusted with the task of drafting part of the celestial chart when it was divided among the various observatories of the two hemispheres; in 1907 he was created cardinal.
With these offices, his merits continued to multiply: his pastoral letters and speeches had wide resonance throughout Italy; for the solid preparation of seminarians, he revived the Faculty of Theology; he promoted Catholic Action in the archdiocese and in Italy, working so that the entire Catholic movement might regain its former unity of organization, from which the Central Board arose; he restored the monumental churches of S. Paolo a Ripa d’Arno, S. Caterina, and S. Francesco; he reconstructed in the Cathedral the pulpit of Giov. Pisano; also in the Cathedral, he brought back the remains of Arrigo VII, and to S. Caterina the relics of B. Giordano da Rivalto. A splendid model of charity during the gravest hours of the fatherland, and a promoter of various works for the needy, especially during and after the First World War, he also rendered invaluable services to the Church and the Fatherland during the years of disagreement between the two powers. After the Lateran Pacts had been concluded, he was invited to bless the marriage of the heir apparent Umberto di Savoia to Maria José del Belgio (8 January 1930), and on the same day he was awarded the collar of the Most Holy Annunciation.
Principal works, besides the numerous articles in Scuola Cattolica and Rivista di scienze fisiche e matematiche: La carta del cielo per mezzo della fotografia (Milan 1892); Il p. fr. Denza, tributo di riconoscenza e di amore (there 1895); La stella dei Magi (there 1895); Commemorazione di A. Volta (Monza 1899); Riflessioni sui nostri doveri davanti alla scienza moderna e alla Fede (2nd ed., Pavia 1899); Scritti vari, Siena 1904; Lettere pastorali, omelie, discorsi (vol. I [1904–11], Turin 1911; II [1912–19], there 1919), which deal with the most varied subjects and the most pressing questions of the time and commemorate figures of scholars and saints; Conversazioni manzoniane con il mio clero (2 vols., Turin 1923).