Erechtheus (; ) in
Greek mythology was the name of an archaic
king of Athens, the founder of the
polis and, in his role as god, attached to
Poseidon, as "Poseidon Erechtheus". The mythic Erechtheus and an historical Erechtheus were fused into one character in
Euripides' lost tragedy
Erechtheus (423/22 BCE). The name
Erichthonius is carried by a son of Erechtheus, but
Plutarch conflated the two names in the myth of the begetting of Erechtheus.