History of the Peloponnesian War

Almost immediately after this, fresh differences arose between the Athenians and Peloponnesians, and contributed their share to the war.

Corinth was forming schemes for retaliation, and Athens suspected her hostility. The Potidaeans, who inhabit the isthmus of Pallene, being a Corinthian colony, but tributary allies of Athens, were ordered to raze the wall looking towards Pallene, to give hostages, to dismiss the Corinthian magistrates, and in future not to receive the persons sent from Corinth annually to succeed them. It was feared that they might be persuaded by Perdiccas and the Corinthians to revolt, and might draw the rest of the allies in the direction of Thrace to revolt with them.