Strabo Geography 8.7.1

[1] In antiquity this country was under the mastery of the Ionians, who were sprung from the Athenians; and in antiquity it was called Aegialeia, and the inhabitants Aegialeians, but later it was called Ionia after the Ionians, just as Attica also was called Ionia ¹ after Ion the son of Xuthus. They say that Hellen was the son of Deucalion, and that he was lord of the people between the Peneius and the Asopus in the region of Phthia and gave over his rule to the eldest of his sons, but that he sent the rest of them to different places outside, each to seek a settlement for himself. One of these sons, Dorus, united the Dorians about Parnassus into one state, and at his death left them named after himself; another, Xuthus, who had married the daughter of Erechtheus, founded the Tetrapolis of Attica, consisting of Oenoe, Marathon, Probalinthus, and Tricorynthus. One of the sons of Xuthus, Achaeus, who had committed involuntary manslaughter, fled to Lacedaemon and brought it about that the people there were called Achaeans; and Ion conquered the Thracians under Eumolpus, and thereby gained such high repute that the Athenians turned over their government to him. At first Ion divided the people into four tribes, but later into four occupations: four he designated as farmers, others as artisans, others as sacred officers, and a fourth group as the guards. And he made several regulations of this kind, and at his death left his own name to the country. But the country had then come to be so populous that the Athenians even sent forth a colony of Ionians to the Peloponnesus, and caused the country which they occupied to be called Ionia after themselves instead of Aegialus; and the men were divided into twelve cities and called Ionians instead of Aegialeians. But after the return of the Heracleidae they were driven out by the Achaeans and went back again to Athens; and from there they sent forth with the Codridae the Ionian colony to Asia, and these founded twelve cities on the seaboard of Caria and Lydia, thus dividing themselves into the same number of parts as the cities they had occupied in the Peloponnesus. Now the Achaeans were Phthiotae in race, but they lived in Lacedaemon; and when the Heracleidae prevailed, the Achaeans were won over by Tisamenus, the son of Orestes, as I have said before, ² attacked the Ionians, and proving themselves more powerful than the Ionians drove them out and took possession of the land themselves; and they kept the division of the country the same as it was when they received it. And they were so powerful that, although the Heracleidae, from whom they had revolted, held the rest of the Peloponnesus, still they held out against one and all, and named the country Achaea. Now from Tisamenus to Ogyges they continued under the rule of kings; then, under a democratic government, they became so famous for their constitutions that the Italiotes, ³ after the uprising against the Pythagoreians, ⁴ actually borrowed most of their usages from the Achaeans. ⁵ And after the battle at Leuctra the Thebans turned over to them the arbitration of the disputes which the cities had with one another; and later, when their league was dissolved by the Macedonians, they gradually recovered themselves. When Pyrrhus made his expedition to Italy, ⁶ four cities came together and began a new league, among which were Patrae and Dyme; ⁷ and then they began to add some of the twelve cities, except Olenus and Helice, the former having refused to join and the latter having been wiped out by a wave from the sea. ⁸