The son of Helios and the brother of Circe and Pasiphae. His son was Sisyphus and his daugther Medea.
He was the king of Colchis, the land near the Black Sea to which Phrixus was carried by a golden ram. Aeetes took care of the boy, and even married one of his daughters to him. To repay Aeetes for his kindness, Phrixus sacrificed sacrificed the golden ram, and gave its golden fleece to the king. Aeetes nailed the fleece to an oak in a grove sacred to Ares, where it would be protected by a fierce dragon.
When Jason arrived to claim the golden fleece, Aeetes had him first complete a test. He had to take the teeth of sacred serpent, yoke two fire-breathing bulls to a plow, plow the soil with the dragon's teeth, and then kill the warriors who sprung up from the ground. Furthermore, if Jason should fell, then all of the Argonauts would be killed.
With the help of a potion from Medea, Jason succeeded.