According to Greek mythology, Zeus wanted Heracles to rule the land of Perseus in Mycenae and Tiryns. However, after the death of Heracles, these cities fell into the hands of the descendants of Pelops and, during the Trojan War, Agamemnon reigned in Mycenae.
The Greeks held as historical fact the legend that two generations after the Trojan War, c. 1100 BC. BC, had taken place an invasion of Greece by a new people coming from the North and speaking Greek, the Dorians. The latter would have accompanied the sons of the hero Heracles, the Heraclides, when they returned to the Peloponnese to claim the inheritance of their father, Tiryns first, then, by conquest, the whole of the Peloponnese.
This legend explained many historical facts; starting with the fact that large parts of Greece were occupied by a Greek people speaking the Doric dialect. The close relationship between Doric and Northwest Greek argues in favor of the legend that the Dorians came from the Northwest, Epirus and Southwest Macedonia, then passed through Thessaly and Boeotia, where some of them settled in that small region of central Greece called Doride, from where they later went south through Delphi, Naupactos in the south-west and from there to the Peloponnese .
Tradition has it that Corinth was one of their last conquests.
The fact that the Arcadian dialect remains very close to Predorian Greek seems to indicate that the Dorian invaders did not succeed in penetrating the most remote regions of Arcadia.
Secondly, the Dorian States presented this particularity of being all divided according to the three tribes of Hyllées, Dymanes and Pamphyliens, which suggests a great sense of identity.
Thirdly, the Dorians were apparently unknown at the time of the Trojan War and Homer does not mention them, although they later occupied the territory already held, according to Homer, by Agamemnon and the Achaeans, and that at Argos and Sparta they ruled over a quasi-slave population of non-Dorian Greeks.
The Dorian invasion can also explain this historical fact to which the Greeks themselves paid little heed, namely that the cities and civilization of Mycenaean Greece were destroyed by successive attacks in the 12th century BC. J.-C. which succeeded the migrations beyond the seas towards Asia Minor, c. 1050-950, as well as scarcity and dispossession in Greece itself.
There is neither archaeological proof of the identity of the people who destroyed the Mycenaean culture, nor tangible signs of the influence of a new people. This is understandable if the invaders came from a Greek stock connected to the fringes of the Mycenaean world.
It has also been argued that there was in fact no Dorian invasion, but that different groups of Greeks had inhabited Greece since the beginning of the Mycenaean culture and that the destruction was due to episodic raids or local insurgencies of a oppressed population.
However, the strong ruptures introduced by these destroyers, as well as the legends themselves, plead in favor of the historicity of the Dorian invasion.