History of the Peloponnesian War

On their arrival, the Athenians, afraid that Aristeus, who had been notably the prime mover in the previous affairs of Potidaea and their Thracian possessions, might live to do them still more mischief if he escaped, slew them all the same day, without giving them a trial or hearing the defence which they wished to offer, and cast their bodies into a pit; thinking themselves justified in using in retaliation the same mode of warfare which the Lacedaemonians had begun, when they slew and cast into pits all the Athenian and allied traders whom they caught on board the merchantmen round Peloponnese. Indeed, at the outset of the war, the Lacedaemonians butchered as enemies all whom they took on the sea, whether allies of Athens or neutrals.

About the same time towards the close of the summer, the Ambraciot forces, with a number of barbarians that they had raised, marched against the Amphilochian Argos and the rest of that country.

The origin of their enmity against the Argives was this.

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.