Iacchus, minor deity associated with the Eleusinian Mysteries, the best known of the ancient Greek mystery religions. On the day preceding the commencement of the mysteries, Iacchus’ name was invoked with the names of the earth goddess Demeter and her daughter Kore (Persephone) during the procession from Athens to Eleusis, a city in Attica. Probably originally a personification of the ritual invocation (Iakch’ ō Iakche), Iacchus was variously identified. According to some sources he was synonymous with Bacchus (a title of the wine god Dionysus), whose name was similar to his. Iacchus was also regarded as the son of Zeus and Demeter (or sometimes as her consort) and differentiated from the Theban Bacchus (Dionysus), who was the son of Zeus and Semele. Still other traditions identified Iacchus as the son of Kore or of Dionysus. In art Iacchus was portrayed holding a torch and leading the celebrants.