Portrait of Clement XII Corsini and Cardinal Neri Maria Corsini

In 1737 Pope Clement XII canonised a group of new saints, among them Vincent de Paul, and his nephew, Cardinal Neri Maria Corsini, acted in the proceedings as procurator, the official who presented the causes of the new saints to the pope. In the family palace on Via della Lungara the cardinal later gathered the paintings connected with the canonisations of his uncle's reign into a single room, the antechamber of the canonisations, and 18th-century inventories record this double portrait there.

It was commissioned in 1738 for the Corsini house, but it was put in place only in 1741, once that part of the building had been finished, by which time the pope was dead. Pietro Paolo Cristofari, head of the mosaic painters of St Peter's, built it from tiny tesserae, and the museum describes it as able to imitate painting so closely that it fools the eye. It follows the official formula for a pope portrayed with his cardinal nephew, the two side by side. The choice of mosaic carried its own message, a material thought incorruptible and eternal that tied the family to ancient Rome and to the Christian Rome of the Middle Ages.