The Cappella Castiglionewas the first chapel in Rome to be frescoed following the election, in 1417, of Cardinal Oddone Colonna as Pope Martin V (r. 1417-31), an election which brought to an end almost fifty years of schism, when the church had more than one claimant to the throne of the Holy See.
The chapel’s patron was Branda Castiglione, a distinguished member of a Milanese family, who was the titular cardinal of San Clemente. The choice of subject-matter reflects the personal history and interests of the patron. Both St Ambrose, patron saint of Milan, scholar and fighter against schism and heresy, and St Catherine, defender of the faith and church orthodoxy, were appropriate models for Castiglione, a leading humanist and a staunch opponent of doctrinal divisions and heresy. The frescoes were painted by Masolino da Panicale (1383-1447) between 1428 and 1432. On the entrance wall of the chapel are images of the Annunciation and St Christopher.