This marble panel, which dates to the second century AD, is one of three moved to the staircase of the Palazzo dei Conservatori by Pope Leo X in 1572. Restored in 1595, it can serve as an example of that process. Originally, the right arm and leg of the emperor were much closer to the horse, and the palm turned up in a gesture of goodwill to the barbarians kneeling before him. It was restored to imitate the hand of the equestrian statue of Marcus Aurelius that had been moved to the Piazza del Campidoglio in 1538. The head of the horse, which has been restored from the jaw upwards and stands in greater relief from the background, also recalls the bronze statue. The right leg of the horse has been lifted as well. These all are deliberate changes, each intended to make the original relief more heroic.
Reference: History of Restoration of Ancient Stone Sculptures (2001) edited by Janet Burnett Grossman, Jerry Podany, and Marion True.
See also the Dying Gaul.
