The relief depicts Marcus Aurelius in an attitude very similar to that which can be seen in the equestrian statue in the centre of the square: on horseback, in military garb, with his right arm outstretched, he exercises his clemency towards the kneeling barbarian prisoners. It probably derives from a triumphal arch dedicated to Marcus Aurelius on the occasion of his victories over the Sarmatians and Germans in 176 A.D.; in the Capitol since 1515, it comes from the Church of Saints Luke and Martina in the Roman Forum.