Santa Maria del Popolo
The architect or architects of this innovative project remain unknown due to a lack of contemporary sources. Giorgio Vasari in his "Lives" attributed all the important papal projects in Rome during Sixtus IV to a Florentine, Baccio Pontelli including the basilica and monastery of Santa Maria del Popolo. Modern researchers deemed this claim highly dubious and proposed other names among them Andrea Bregno, a Lombard sculptor and architect whose workshop certainly received important commissions in the basilica. The fundamental differences between the façade and the interior suggest that maybe more than one architect was working on the building.
Roman Renaissance
The last part of this century was dominated by the figure of Pope Alexander VI, from the Spanish family Borgia. He first turned his attention to the defence of the Eternal City. He changed the Mausoleum of Adrian into a fortress, likewise Torre di Nona, to secure the city from naval attacks. His Via Alessandrina, now called Borgo Nuovo, remains to the present day the grand approach to St. Peter's. Though a scandalous pope, he was a patron of the arts and sciences, and in his days a new architectural era was initiated in Rome with the coming of Bramante. Raphael, Michelangelo and Pinturicchio. He commissioned Pinturicchio to lavishly paint a suite of rooms in the Apostolic Palace in the Vatican, which are today known as the Borgia Apartments. In addition to the structures erected by himself, his memory is associated with the many others built by monarchs and cardinals at his instigation. During his reign Bramante designed for Ferdinand and Isabella the Tempietto, on the traditional site of St. Peter's martyrdom. Bramante, or some other great architect, built for Cardinal Riario the palace of the Cancellaria. In 1500, the ambassador of Emperor Maximilian laid the cornerstone of the national church of the Germans, Santa Maria dell' Anima, the French Cardinal Briçonnet erected SS. Trinità dei Monti, and the Spaniards Santa Maria di Monserrato. To Alexander we owe the beautiful ceiling of Santa Maria Maggiore, in the decoration of which he employed the first gold brought from America by Columbus.