History of the Peloponnesian War

This Argos and the rest of Amphilochia were colonized by Amphilochus, son of Amphiaraus. Dissatisfied with the state of affairs at home on his return thither after the Trojan war, he built this city in the Ambracian gulf, and named it Argos after his own country.

This was the largest town in Amphilochia, and its inhabitants the most powerful.

Under the pressure of misfortune many generations afterwards, they called in the Ambraciots, their neighbors on the Amphilochian border, to join their colony; and it was by this union with the Ambraciots that they learnt their present Hellenic speech, the rest of the Amphilochians being barbarians.