Jason is motivated in his search by his evil uncle Pelias who tells him the story of the Golden Fleece. In this story, a golden ram was sent by the gods to save two children from their evil stepmother. The boy allowed the ram to be killed for its golden fleece, angering the gods who sent a curse on his family. Pelias suggests that Jason go on a quest for the fleece and that if Jason succeeds, Pelias will give Jason his kingdom (the kingdom to which Jason is actually the rightful heir.)

The motives involved are:

• Pelias is hoping that Jason will die on the quest so Pelias can keep the throne securely.
• Jason believes that Pelias will give him the throne if he brings back the fleece. 
• Jason is young and untested and by completing a dangerous heroic adventure, he will prove himself worthy of the throne.
• Fame and glory were very important in Greek heroic culture.