Under the Severans, from Septimius Severus (193—212) to Alexander Severus (222—235), Rome continued to play a central role in the cultural policy of the emperors. Major monuments were built. Foreign works of art, mainly of Asian origin, continued to be imported, and artists flocked to the city, particularly from Hellenistic centres. There was a notable import trade in sculpted marble sarcophagi. A wreck from the first half of the third century, found off Taranto, was carrying a cargo of twenty-four such items from the Eastern Mediterranean. The carvings on sarcophagi were imbued with a new spirituality, combining symbolism, mythology and oriental religion, and thus preparing the way for Christian themes. In the private iconography of sarcophagi, we now find the same relationship as had previously existed between the public figure and his portrait in official sculpture, with the deceased often represented taking part in hunting or battle scenes. The entire third century is rich in fine sarcophagi. The Ludovisi sarcophagus, for instance, at the Museo delle Terme, which dates from the early part of the century, features a true likeness of the deceased in the guise of a victorious warrior. At the same time, there was a vogue for pastoral or bucolic scenes covering all sides of the sarcophagus, which was another step on the road to Christian iconography.

Two outstanding works of public sculpture survive from the Severan period. The first, the gateway known as the Silversmiths’ Arch, was erected in 204 AD at the entrance to the Forum Boarium, the former business centre of Republican Rome. The monument in many ways anticipates Late Antique sculpture: the emperor and empress, who occupy almost all the available space, are depicted frontally, without depth, while foliage elements play an important part in the decoration. The chief monument of this period is, nevertheless, the Arch of Septimius Sevens, erected in the Roman Forum in 203 AD. It consists of three openings framed by free—standing columns on imposing bases, and an uninterrupted upper storey bearing the inscription. The four large historical reliefs above the lateral arches tell of Septimius Severus’s campaigns in Mesopotamia. These panels continue the Roman tradition of historical relief sculpture. According to Herodian, the military scenes were, inspired by paintings the Emperor sent to the Senate. Stylistically, they exhibit definite links with the reliefs of the columns of Trajan and Marcus Aurelius, particularly the latter. However, the carved subjects are more isolated, in keeping with the general trend of official sculpture in the first quarter of the third century. Public relief sculpture and private sarcophagi were now developing on parallel lines and drawing on similar subject matter. The Palazzo Mattei sarcophagus, carved with hunting scenes, shows the direction things were taking in the second quarter of the century. It is sarcophagi of this type that enable us to follow the various stylistic trends of the period. In imperial portraits, too, we can chart a gradual liberation from Classical canons and at the same time the emergence of a new physical and psychological individualism.

During the third century, the provinces began to evolve sculptural forms of their own. Independence was in the air, encouraging the development of local styles, which were eventually to influence the art of Rome itself The materials and techniques used by local craftsmen were an important factor in the process of differentiation. From the time of Gallienus (253—268) until the Tetrarchy, Roman art abandoned the Hellenistic tradition and forms evolved in a new climate of artistic freedom. Not until the rime of Constantine did the Empire rediscover its unity this time under the influence of Christianity.