The hero who sailed on the Argo in search of the Golden Fleece is Jason. Accompanied by a band of heroes known as the Argonauts, Jason's quest was not just for glory, but also to reclaim his rightful throne. The journey symbolizes themes of adventure, bravery, and the pursuit of destiny. Jason's encounters with various challenges, including the sorceress Medea, further illustrate the complexities of heroism and the consequences of ambition in Greek mythology.