This portrait of emperor Antoninus Pius (138-161 A.D.), whose serene features and eyes veiled with a subtle melancholy reflect the meek character, inclined towards mercy and moderation that the ancient biography of the Historia augusta described as his particular virtues. In spite of the period of his reign, noted as one of the longest in Roman history, there are relatively few of these official portraits of Antoninus Pius, which were mostly made for special occasions, such as anniversaries, triumphs, or appointments as consul, and promptly distributed in hundreds of copies throughout the provinces in the empire. Of the three sub-types of the only type of portrait known for this emperor, the one known as “Formia” is considered the closest to the official model; it is this one that the Florentine version seems to produce here, especially due to the way the hair falls over the forehead, with a pair of curls in the centre, and others combed into a dovetail at the sides. Compared to the majority of Roman portraits that are still preserved today, where heads are often placed on modern busts, the Antoninus Pius in Palazzo Pitti has a head that is one piece with the original bust; this is dressed in a fringed army cloak (known as a paludamentum). The only elements that can be attributed to modern additions are the right sleeve, some drapes, and the large buckle on the cloak, fastened over the right shoulder.