It appears to have derived its name from the supposed advent (ἔλευσις) of Demeter, though some traced its name from an eponymous hero Eleusis. It was one of the 12 independent states into which Attica was said to have been originally divided. It was related that in the reign of Eumolpus, king of Eleusis, and Erechtheus, king of Athens, there was a war between the two states, in which the Eleusinians were defeated, whereupon they agreed to acknowledge the supremacy of Athens in every thing except the celebration of the mysteries, of which they were to continue to have the management. Eleusis afterwards became an Attic deme, but in consequence of its sacred character it was allowed to retain the title of "polis" (πόλις) and to coin its own money, a privilege possessed by no other town in Attica, except Athens. The history of Eleusis is part of the history of Athens. Once a year the great Eleusinian procession travelled from Athens to Eleusis, along the Sacred Way.