In ancient Greek religion and mythology, Iacchus (also Iacchos, Iakchos) (Ancient Greek: Ἴακχος) was a minor deity, of some cultic importance, particularly at Athens and Eleusis in connection with the Eleusinian mysteries, but without any significant mythology.[1] He perhaps originated as the personification of the ritual exclamation Iacche! cried out during the Eleusinian procession from Athens to Eleusis.[2] He was often identified with Dionysus, perhaps because of the resemblance of the names Iacchus and Bacchus, another name for Dionysus. By various accounts he was a son of Demeter (or apparently her husband), or a son of Persephone, identical with Dionysus Zagreus, or a son of Dionysus.
During the Greco-Persian Wars, when the Attic countryside, deserted by the Greeks, was being laid waste by the Persians, a ghostly procession was supposed to have been seen advancing from Eleusis, crying out “Iacchus”. This miraculous event was interpreted as a sign of the eventual Greek victory at the Battle of Salamis (480 BC).[3] Iacchus was also possibly involved in an Eleusinian myth in which the old woman Baubo, by exposing her genitals, cheered up the mourning Demeter.