The Heracleidae or Heraclids were the numerous descendants of Heracles holding (Hercules), especially applied in a narrower sense to the descendants of Hyllus, the eldest of his four sons by Deianira. Other Heracleidae included Macaria, Lamos, Manto, Bianor, Tlepolemus, and Telephus. These Heraclids were a group of Dorian kings who conquered the Peloponnesian kingdoms of Mycenae, Sparta and Argos; according to the literary tradition in Greek mythology, they claimed a right to rule through their ancestor. Since Karl Otfried Müller's Die Dorier, I. ch. 3, their rise to dominance has been associated with a "Dorian invasion". Though details of genealogy differ from one ancient author to another, the cultural significance of the mythic theme, that the descendants of Heracles, exiled after his death, returned some generations later to reclaim land that their ancestors had held in Mycenaean Greece, was to assert the primal legitimacy of a traditional ruling clan that traced its origin, thus its legitimacy, to Heracles.

Heracles, born Alcaeus or Alcides, was a divine hero in Greek mythology, the son of Zeus and Alcmene, and the foster son of Amphitryon. He was a descendant and half-brother of Perseus. He was the greatest of the Greek heroes, the ancestor of royal clans who claimed to be Heracleidae (Ἡρακλεῖδαι), and a champion of the Olympian order against chthonic monsters. In Rome and the modern West, he is known as Hercules, with whom the later Roman emperors, in particular Commodus and Maximian, often identified themselves. Details of his cult were adapted to Rome as well.