Who is Perseus?

As Perseus grew into manhood, Polydectes developed a desire for Danaë and came to see her son as an obstacle. Perseus, suspicious of the king's intentions, shielded his mother from him. Polydectes responded by staging an elaborate banquet at which every guest was expected to bring a gift, ostensibly to help him court Hippodamia, daughter of Oenomaus. When asked what gift he thought fitting, Perseus rashly declared he would bring the head of Medusa, the Gorgon whose gaze turned onlookers to stone. In another version of events, Perseus had already offered to fetch Polydectes any gift he named, however difficult.

When the other guests arrived with horses and Perseus had nothing comparable to offer, Polydectes rejected his gift and held him to his boast, sending him off to retrieve Medusa's head, a task seemingly designed to get rid of him for good.

Medusa was one of three Gorgon sisters, monstrous women with snakes for hair, golden wings, sharp claws, and a stare that turned any living thing to stone. Unlike her sisters Stheno and Euryale, she was mortal. Before Perseus set out, he prayed to the gods, and Zeus sent two of his other children to equip his son for the task. Hermes lent Perseus winged sandals and the curved sword known as the harpe, while Hades contributed his helm of invisibility. Athena gave Perseus a polished shield, so he could track Medusa by her reflection rather than look at her directly, along with a special pouch, the kibisis, to carry the severed head safely, since it retained its petrifying power even after death.

Athena directed Perseus first to the Graeae, three elderly sisters who shared a single eye and tooth between them. Perseus seized the eye as they were passing it from one to another and refused to return it until they told him where to find the Gorgons. With that information, he traveled to the island of Sarpedon, where he found the Gorgons asleep. Walking backward and guiding himself by the shield's reflection, he approached Medusa and beheaded her with Athena steadying his aim. From her severed neck sprang Pegasus and Chrysaor, her children by Poseidon. Stheno and Euryale woke and pursued him, but the helm of invisibility let him escape. On his way home he also turned King Atlas to stone with the Gorgon's head after being refused hospitality, an act later connected to the origin of the Atlas mountains.

Flying homeward, Perseus passed through the kingdom of Aethiopia, ruled by Cepheus and Cassiopeia. Cassiopeia had boasted that her daughter Andromeda surpassed the Nereids in beauty, provoking Poseidon to send a flood and a sea monster, Cetus, to ravage the land. An oracle declared that the only remedy was to sacrifice Andromeda to the creature, so she was chained to a rock on the shore. Perseus arrived in time to kill the monster, either with the harpe or by turning it to stone with Medusa's head, and claimed Andromeda as his wife, overriding her previous betrothal to Phineus, who was later petrified when he challenged the marriage.

Returning at last to Seriphos, Perseus found that his mother had been forced to seek refuge from Polydectes' unwanted advances. He confronted the king and used Medusa's head to turn him to stone, then installed Dictys, the fisherman who had raised him, as the island's new ruler. Having no further need of the weapons lent to him, Perseus returned them and gave Medusa's head to Athena, who mounted it on her aegis.

Accounts differ on how Acrisius eventually died, but all agree the oracle's warning came true. In one version, Perseus never returned to Argos at all; instead he traveled to Larissa to compete in athletic games, where he had just introduced the discus throw. Acrisius, visiting the games, was struck and killed by Perseus's throw, fulfilling the prophecy without any direct confrontation between them. Another account has Acrisius fleeing to Thessaly on hearing of his grandson's approach, only to be killed there in the same accidental manner during funeral games. Either way, Perseus did not kill his grandfather deliberately.

Perseus, now heir to the Argive throne, chose not to rule Argos directly, reportedly out of discomfort at having gained the kingdom through his grandfather's death. He traded kingdoms with Megapenthes, taking Tiryns for himself while Megapenthes took Argos. Greek tradition credited Perseus with founding Mycenae, and later writers pointed to a shrine and sacred spring associated with him there. Through his marriage to Andromeda, Perseus fathered several sons and daughters, and their descendants, the Perseids, ruled Mycenae for generations, eventually including Heracles among their line.