Return of the Heracleidae

The Dorian invasion is a concept devised by historians of Ancient Greece to explain the replacement of pre-classical dialects and traditions in southern Greece by the ones that prevailed in Classical Greece. The latter were named Dorian by the ancient Greek writers, after the Dorians, the historical population that spoke them.

Greek legend asserts that the Dorians took possession of the Peloponnesus in an event called the Return of the Heracleidae (Ancient Greek: Ἐπιστροφὴ τῶν Ἡρακλειδῶν). Classical scholars saw in the legend a possibly real event they termed the Dorian invasion. The meaning of the concept has changed several times, as historians, philologists and archaeologists used it in attempts to explain the cultural discontinuities expressed in the data of their fields. The pattern of arrival of Dorian culture on certain islands in the Mediterranean, such as Crete, is also not well understood. The Dorians colonised a number of sites on Crete such as Lato.

Despite nearly 200 years of investigation, the historicity of a mass migration of Dorians into Greece has never been established, and the origin of the Dorians remains unknown. Some have linked them or their victims with the emergence of the equally mysterious Sea Peoples. The meaning of the phrase "Dorian invasion" as an explanation for the cultural break after the Mycenaean period has become to some degree amorphous. Investigations into it have served mainly to rule out various speculations, though the possibility of a real Dorian invasion remains open.

Classical tradition, as recorded for example in Herodotus, describes the "Return of the Heracleidae" (Ἐπιστροφὴ τῶν Ἡρακλειδῶν), the descendants of Heracles, who were exiled at his death and returned in later generations to reclaim the dominion that Heracles had held in the Peloponnesus. The Greece to which the tradition refers is the mythic one, now considered to be Mycenaean Greece. The details differ from one ancient author to another, the commonality being that a traditional ruling clan traced its legitimacy to Heracles.

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