Martin V, who reigned from 1417 to 1431 as the first pope of the Roman Catholic church newly reunited after a long schism, set about rebuilding and ornamenting the degraded city of Rome. As a consequence, many artists, including Masaccio and Masolino from Florence, were attracted by commissions to Rome. The two worked on an altarpiece for the basilica of Santa Maria Maggiore. This image of Saints Paul and Peter is one of two panels in the Museum that were originally opposite sides of a single section of the altarpiece. They were begun by Masaccio and finished by Masolino after the former's untimely death at age twenty-seven. Masolino's task was not an easy one, because he was asked to reverse the saints' positions. Masolino made the requested modifications, but did so by incorporating what work Masaccio had finished. In Saints Paul and Peter, for example, he carefully painted around the already executed hands, feet, and blue drapery to adapt Masaccio's design to the new iconography. Carl Brandon Strehlke, from Philadelphia Museum of Art: Handbook of the Collections (1995), p. 163.