One detail gives an unambiguous clue to the subject. Just above the male head is a knobbed stick or wand – a 'thyrsus' brandished by the wine-god Bacchus and his devotees during their orgiastic ritual celebrations. Is it too fanciful to imagine that the painting showed the god himself, dancing with female worshippers, framed by the sea-horses of Neptune or the chariot of the sun-god Apollo?
Perhaps dating to the 2nd century AD, the painting may have come from a bath-house or the dining room of a wealthy town-house. Because the plaster was discovered in dumps of rubble, we do not know exactly where the building was, though it was probably situated nearby.
This is not the only example of Bacchus being a feature of interior design. A large mosaic found in Leadenhall Street in 1803 formed the floor of a room more than 6m (20feet) square with the design set within a wide border of plain red tesserae. The finely-executed central portion is now preserved in the British Museum and features Bacchus riding on a tiger. Elements of his features are picked out in blue glass tesserae, indicating that it is mosaic of some quality.
A version of this article appeared in Archaeology Matters No 17, March 2002
For further information about wall paintings, see Internal walls in Home life.