Nephew, of Antonio da Sangallo, the Elder. Born in Mugello, Italy April 12, 1484; died in Terni, Italy in August 3, 1546. Working for 41 years under the patronage of Pope Leo X, Pope Clement VII, and Pope Paul III, he exhibited extraordinary ability as a builder of churches and palaces, and as a military engineer. He succeeded his master Bramante in the building of Saint Peter's, completed the church of Madonna di Loreto, and erected at Borgo the church of San Spirito. The most notable of his palaces are Palazzo Farnese, Palazzo Sacchetti, and Villa Madama. He filled numerous engineering commissions in various Italian cities and cut the Pozzo di San Patrizio (Saint Patrick's Well) at Orvieto.