Cocidius was a deity worshipped in northern Britain.
The Romans equated him with Mars and also with Silvanus. Like Belatucadrus, he was probably worshipped by lower-ranked Roman soldiers as well as by the Britons for whom he was probably a tribal god.
There are at least nine representations known in the Hadrian’s Wall corridor, and a further twenty five or so inscriptions dedicated to him. Most of these are along the western portion of the Wall, the most spectacular being found at Yardhope, where a figure in bas-relief brandishes spear and shield on a vertical rock-face at the entrance to a small shrine.