Her origins are obscure. Nonnus calls her a nymph,[2] while according to Stephanus, she was called Iope, the daughter of Aeolus, from whom the town of Joppa (now the Jaffa neighborhood in Tel Aviv) derived its name.[3]
Mythology
Cassiopeia boasted that she (or her daughter Andromeda), was more beautiful than all the Nereids, the nymph-daughters of the sea god Nereus. This brought the wrath of Poseidon, ruling god of the sea, upon the kingdom of Aethiopia.[4]
Accounts differ as to whether Poseidon decided to flood the whole country[5] or direct the sea monsterCetus to destroy it. In either case, trying to save their kingdom, Cepheus and Cassiopeia consulted a wise oracle, who told them that the only way to appease the sea gods was to sacrifice their daughter.
Accordingly, Andromeda was chained to a rock at the sea's edge and left to be killed by the sea monster. Perseus arrived and instead killed Cetus, saved Andromeda and married her.[5]
Poseidon thought Cassiopeia should not escape punishment, so he placed her in the heavens chained to a throne in a position that referenced Andromeda's ordeal. The constellation resembles the chair that originally represented an instrument of torture. Cassiopeia is not always represented tied to the chair in torment; in some later drawings she holds a mirror, symbol of her vanity, while in others she holds a palm frond.[6][7][8]
Constellation
The constellation Cassiopeia, near to the pole star, can be seen from latitudes north of 35°N during the whole year. The constellation is also visible in countries north of the Tropic of Capricorn, in late spring.
Ethiopian tradition
According to the 1922 regnal list of Ethiopia, Cassiopeia ruled Ethiopia as part of the Agdazyan dynasty and reigned for 19 years from 1890 to 1871 BC, with dates following the Ethiopian calendar.[9]
^Tripp, s.v. Cassiopeia. According to Apollodorus, 2.4.3, and Hyginus, De Astronomica2.10, Cassiopeia boasted that she was more beautiful, while according to Hyginus, Fabulae64, it was that her daughter Andromeda was more beautiful.
Stephanus of Byzantium, Stephani Byzantii Ethnicorum quae supersunt, edited by August Meineike (1790-1870), published 1849. A few entries from this important ancient handbook of place names have been translated by Brady Kiesling. Online version at the Topos Text Project.
Tripp, Edward, Crowell's Handbook of Classical Mythology, Thomas Y. Crowell Co; First edition (June 1970). ISBN069022608X.