An Argive princess, she was an ancestor of many kings and heroes, such as Perseus, Cadmus, Heracles, Minos, Lynceus, Cepheus, and Danaus.

[6] Io's father was called Peiren in the Catalogue of Women,[7] and by Acusilaus,[8] possibly a son of the elder Argus, also known as Peiras, Peiranthus or Peirasus.

In the version of the myth told in Prometheus Bound she initially rejected Zeus' advances, until her father threw her out of his house on the advice of oracles.

Pitying the unfortunate girl, Gaia, the goddess of the earth, created the violet (Ancient Greek: ἴον, romanized: ion), so the cow could eat, thus growing "from her from whom it has its name", based on incorrect folk etymology.

Io eventually crossed the path between the Propontis and the Black Sea, which thus acquired the name Bosporus (meaning ox passage), where she met Prometheus, who had been chained on Mt.

Their grandson, Danaus, eventually returned to Greece with his fifty daughters (the Danaids), as recalled in Aeschylus' play The Suppliants.

The myth of Io must have been well known to Homer, who often calls Hermes Argeiphontes, which is often translated as "Argus-slayer", though this interpretation is disputed by Robert Beekes.

[23] According to the Dictionary of Greek and Roman Biography and Mythology by William Smith, Io at some point landed at Damalis, and the Chalcedonians erected a bronze cow on the spot.