(b. 1492, San Gimignano, d. 1530, San Gimignano)
Italian painter. He was a pupil of Sodoma, whom he assisted on the frescoes in the monastery of Monte Oliveto Maggiore, near Siena. In 1510-12 he executed frescoes of the Virgin and Child with Saints and Others in the ex-pharmacy of the Ospedale di Santa Maria della Croce at Montalcino (Siena) and these show clearly the influence of Sodoma. He then moved to Rome, where he entered the shop of Raphael and probably worked on the decoration of the Loggetta of Cardinal Bernardo Bibbiena in the Vatican; his frescoes of 1516 in the apse of Santa Maria at Arrone (Terni) reflect contemporary Roman ideas, in particular from Raphael's Vatican Stanze and from Baldassare Peruzzi. He then assisted in the decoration of the Vatican Logge, where, on the basis of the frescoes at Arrone, several scenes can be attributed to him, including the Anointing of David, the Adoration of the Magi and the Last Supper. According to Vasari, he also decorated façades (destroyed) of numerous Roman houses.
On his return to San Gimignano in 1522, Tamagni executed a Virgin and Child Enthroned for San Gerolamo, and in 1523 the Birth of the Virgin for Sant'Agostino. Also from this period is the Assumption of the Virgin in the Badia at Isola (Siena) and the Virgin and Child with Saints in the parish church of Pomarance, signed and dated 1525. About this date he returned to Rome, where he completed three ceiling frescoes at Villa Lante, of illustrious men and women surrounded by grotesque decoration.
After the Sack of Rome in 1527, he returned to San Gimignano, where he executed works including the Mystic Marriage of St Catherine (San Gimignano, Biblioteca Comunale) and the Meeting of Joachim and Anne (San Salvatore, Istia d'Ombrore, Grosseto), signed and dated 1528.