 After the return of the Argonauts, Acastus's sisters were manipulated by Medea to cut their father Pelias in pieces and boil them.Acastus, when he heard this, buried his father, and drove Jason and Medea from Iolcus (and, according to Pausanias, his sisters also), and instituted funeral games in honor of his father.He thereafter became king of Iolcus.