History of the Peloponnesian War

These precautionary measures with regard to the Potidaeans the Athenians began to adopt immediately after the sea-fight at Corcyra.

For the Corinthians were now openly at variance with then; and Perdiccas the son of Alexander, king of the Macedonians, had been made their enemy, though he was before an ally and a friend.

He became such, because the Athenians had made an alliance with his brother Philip and Derdas, when acting together against him.

And being alarmed, he both sent to Lacedaemon, and tried to contrive that they might be involved in war with the Peloponnesians, and endeavoured to win over the Corinthians, with a view to Potidaea's revolting;

and made proposals also to the Thrace-ward Chalcidians and the Bottiaeans to join in the revolt, thinking that if he had in alliance with him these places on his borders, he should more easily carry on the war in conjunction with them.

The Athenians perceiving these things, and wishing to anticipate the revolt of the cities, as they happened to be sending out thirty ships and a thousand heavy-armed against his country, with Archestratus, the son of Lycomedes, as general with ten others, gave orders to the commanders of the fleet to take hostages of the Potidaeans, and throw down the wall, and keep a watchful eye over the neighbouring cities, to prevent their revolting.