In Greek mythology Andromeda is the daughter of Cepheus and Cassiopeia, king and queen of ancient Ethiopia. Her mother Cassiopeia foolishly boasts that she is more beautiful than the Nereids, a display of hubris by a human that is unacceptable to the gods. To punish the queen for her arrogance, Poseidon floods the Ethiopian coast and sends a sea monster named Cetus to ravage the kingdom's inhabitants. In desperation, King Cepheus consults the oracle of Ammon, who announces that no respite can be found until the king sacrifices his daughter, Andromeda, to the monster. She is thus chained to a rock by the sea to await her death.