Medusa was one of three sisters born to Phorcys and Ceto known as the Gorgons. According to Hesiod's Theogony, the Gorgons were the sisters of the Graiai and lived in the utmost place towards the night by the Hesperides beyond Oceanus. Later authors such as Herodotus and Pausanias place the Gorgons' abode in Libya. The Gorgon sisters were Sthenno, Euryale, and Medusa; Medusa was mortal while her sisters were immortal.

Beyond the Gorgon's birth, there is little mention of the Gorgons as a group, but Medusa has several myths about her life and death. The most famous of these myths concern her death and demise. In Hesiod's Theogony, he recounts how Perseus cut off the head of Medusa and from her blood sprang Chrysaor and Pegasus, Chrysaor being a golden giant and Pegasus the famous white winged-horse.