The Return of the Heracleidae is an ancient Greek myth concerning the return of the descendants of the hero Heracles to the Peloponnese, Heracles's homeland, and their conquest of various realms in the region. In the myth, Heracles was assisted by the Dorians: the story served as an aetiological myth for the Dorian communities of the Peloponnese, particularly Sparta.
According to the myth, Heracles's children (the Heracleidae) were forced from the Peloponnese by Eurystheus, and settled in the northern Greek region of Thessaly, where Hyllus, Heracles's eldest son, formed an allegiance with the Dorians. The Heracleidae killed Eurystheus, with Athenian support and protection, but Hyllus's attempt to retake the Peloponnese ended in failure and his own death in battle. Following the advice of the Oracle of Delphi, Hyllus's great-grandson, Temenos, led his relatives in a successful invasion, fifty years later, with the help of the Dorians and Oxylus. Temenos then divided the kingdoms of the Peloponnese between himself (receiving Argos), his brother Cresphontes (who received Messenia), and Eurysthenes and Procles, the sons of his brother Aristodemus, who had been killed before the Heracleidae reached the Peloponnese. Eurysthenes and Procles jointly received the kingdom of Sparta, founding the city's dual royal lineage.