(Ἡρακλεῖδαι), a patronymic from Heracles, and consequently given to all the sons and descendants of the Greek Heracles; but the name is also applied in a narrower sense to those descendants of the hero who, in conjunction with the Dorians, invaded and took possession of Peloponnesus.
The many sons of Heracles are enumerated by Apollodorus (2.7.8), though his list is very far from being complete; and a large number of tribes or noble families of Greece traced their origin to Heracles. In some of them the belief in their descent from Heracles seems to have arisen only from the fact, that the hero was worshipped by a particular tribe. The principal sons and descendants of Heracles are treated of in separate articles, and we shall here confine ourselves to those Heracleidae whose conquest of Peloponnesus forms the transition from mythology to history. It was the will of Zeus that lleracles should rule over the country of the Perseids, at Mycenae and Tiryns. Through Hera's cunning, however, Eurystheus had been put into the place of Heracles, and the latter had become the servant of the former. After the death of the two, the claims of Heracles devolved upon the sons and descendants of Heracles. The leader of these Heracleidae was Hyllus, the eldest of the four sons of Heracles by Deianeira. The descendants of Heracles, who, according to the tradition of the Dorians (Hdt. 5.72), were in reality Achaeans, ruled over Dorians, as Heracles had received for himself and his descendants one third of the dominions of the Doric king, Aegimius, for the assistance he had given him against the Lapithae. The countries to which the Heracleidae had especial claims were Argos, Lacedaemon, and the Messenian Pylos, which Heracles himself had subdued : Elis, the kingdom of Augeas, might likewise be said to have belonged to him. (Apollod. 2.7.2, &c.; Paus. 2.18.6, &c., 5.3.1, &c.) The Heracleidae, in conjunction with the Dorians, invaded Peloponnesus, to take possession of those countries and rights which their ancestor had duly acquired. This expedition is called the return of the Heracleidae, κάθοδος τῶν Ἡρακλειδῶν. (Comp. Thuc. 1.12; Isocrat. Archid. 6.) They did not, however, succeed in their first attempt; but the legend mentions five different expeditions, of which we have the following accounts. According to some, it happened that, after the demise of Heracles, his son, Hyllus, with his brothers and a band of Arcadians, was staving with Ceyx at Trachis. As Eurystheus demanded their surrender, and Ceyx was unable to protect them, they fled to various parts of Greece, until they were received as suppliants at Athens, at the altar of Eleos, Mercy, (Apollod. 2.8.1; Diod. 4.57; Paus. 1.32.5; Longin. 27). According to the Heracleidae of Euripides, the sons of Heracles were at first staying at Argos, and thence went to Trachis, Thessaly, and at length to Athens. (Comp. Ant. Lib. 33.) Demophon, the son of Theseus, received them, and they settled in the Attic tetrapolis. Eurystheus, to whom the Athenians refused to surrender the fugitives, now made war on the Athenians with a large army, but was defeated by the Athenians under Iolaus, Theseus, and Hyllus, and was slain with his sons. Hyllus took his head to his grandmother, Alcmene; and the Athenians of later times showed the tomb of Eurystheus in front of the temple of the Pallenian Athena. The battle itself was very celebrated in the Attic stories as the battle of the Seironian reck, on the court of the Saronie gulf (comp Dem. de Coron.
Such are the traditions about the Heracleidae and their conquest of Peloponnesus. The comparatively late period to which these legends refer is alone sufficient to suggest that we have not before us a purely mythical story, but that it contains a genuine historical substance, notwithstanding the various contradictions contained in the accounts. But a critical examination of the different traditions belongs to a history of Greece, and we refer the reader to Müller's Dorians, book i. chap. 3; Thirlwall, Hist. of Greece, vol. i. p. 282, &c., 8vo edit.; Bernardi ten Haar, Commentatio praemio ornata, qua respubl. ad quaestionem : Enarrentur Heraclidarum incursiones in Peloponnesum eorumque causae atque effectus exponantur, Groningen, 1830.
[L.S]