Ocelus was Celtic god known from three inscriptions in Roman Britain.
He seems to have been a British, perhaps a Silurian god, associated with Mars, probably in the latter’s Celtic capacity as a protector. At Caerwent he is linked with Mars Lenus, a Treveran healing deity, and with Vellaunus, who is recorded among the Gaulish Allobroges.
Digital Maps of the Ancient World 