This constellation is sometimes identified as Amalthea, the goat that suckled the infant Zeus after his mother Rhea saved him from being devoured by his father Cronos in Greek mythology. The goat's broken horn was transformed into the cornucopia or horn of plenty. Some ancient sources claim that this derives from the sun "taking nourishment" while in the constellation, in preparation for its climb back northward.

However, the constellation is often depicted as a sea-goat, a goat with a fish's tail. One myth that deals with this says that when the goat-god Pan was attacked by the monster Typhon, he dove into the Nile; the parts above the water remained a goat, but those under the water transformed into a fish.

In Sumeria, the constellation was associated with the god Ea or Enki, who brought culture out of the sea to humankind.

The constellation, together with its early Greek name, associated ideas about sin, and the constellation of Aquarius, who was said to have poured out a river, may represent the origin of the myth of the Augean Stable, which forms one of The Twelve Labours of Herakles.

The constellation is located in an area of sky called the Sea or Water, consisting of many watery constellations such as Aquarius, Pisces, and Eridanus.