This panel depicts Saint Peter Martyr, dressed in the characteristic black and white robes of the Dominican Order, and recognisable from the bloody wound upon his head. According to legend, the Saint was martyred by two assassins who struck his head with an axe. This panel was probably part of a flanking pilaster of an altarpiece frame, the tower-like structure of panels either side of an altarpiece.

Fra Angelico was first recorded as a painter in 1417, around the same time that he became a novice of the Dominican monastic order at the Friary of San Domenico at Fiesole, near Florence. As well as carrying out commissions within the Dominican community, Fra Angelico's clientele included patrons such as the influential Medici family in Florence, and Pope Eugenius IV and Pope Nicholas V in Rome.