On a wall in the Museum in Trier is this relief of Epona
I have long known about it from books, and the fact that it was part of a shrine to Epona in the sacred precinct of the Roman town, where sites of worship are thought to have continued from pre-Roman Gaul. It would then have been in the territory of the Treveri, a tribe who inhabited an area around the Moselle valley west of the Rhine, overlapping current borders between Belgium, Germany and Luxembourg. I managed to find my way to the town to view the relief for myself. It is located in a room in the Museum dedicated to representations of Roman and Celtic deities. After spending some time with Epona, I turned my attention to some of the other gods depicted here.
Many were Roman and Mercury predominates in the particular way he does in Gaul. On one large stone column he is shown on one face together with a female figure who is much worn away but is identified as Rosmerta. On another face of the same column is the figure of Esus apparently using an axe to cut a (willow?) tree in the crown of which there are three birds (cranes or egrets?) and the head of a bull. Parts of this face of the column are also much worn away so the imagery is not clear, but it has been taken to be the same scene as on another monument in Paris where a bull with three cranes has the inscription ‘Tarvos-Trigaranus’ (‘Bull with Three Cranes’) and where Esus is also represented. These are tantalising survivals of the religious imagery of Gaul filtered through Roman representations but remaining mysterious as to their significance.
Next to this column there is also a statue of Sirona, a goddess with a snake around her arm and pointing to what appear to be two eggs in her other hand, one of them broken open:
This compelled my attention for some time. As Rosmerta is often paired with a god the Romans equated with Mercury (Lugus?), so Sirona is similarly often paired with Apollo (Maponos?). I have often pondered the significance of this transference of male god names to fit Roman ‘equivalents’ while the female gods retain their native names. Sirona is represented alone here and has been identified as a goddess of fertility and of healing because of her iconography and the location of shrines by healing springs. That snake winding around her arm might have those associations but also draws attention to those same mysteries of significance which beckon from behind the veil of romanised representation and the views of modern interpreters.
The pagan shrines in the sacred precinct in Trier continued to be used for some time after the establishment of christianity as the official religion of the Roman Empire. They were largely destroyed after the suppression of paganism by the emperor Gratian late in the 4th century. But their survival until then suggests a continuing veneration of the native gods by the descendants of the Treveri, and the neighbouring Mediomatrici, in this part of Gaul.