History of the Peloponnesian War

Thucydides

Thucydides, Vol. 1-4. Smith, Charles Foster, translator. London and Cambridge, MA: Heinemann and Harvard University Press, 1919-1923.

It was in this manner that Brasidas succeeded in rushing through Thessaly before anyone could get ready to hinder him and reached Perdiccas and the Chalcidic peninsula.

The reason why the peoples in Thrace who had revolted from Athens had, in conjunction with Perdiccas, brought this army all the way from the Peloponnesus was that they were filled with alarm at the success of the Athenians. The Chalcidians thought that the Athenians would take the field against them first, and the cities in this neighbourhood which had not yet revolted nevertheless took part secretly in inviting the Peloponnesians to intervene. As for Perdiccas, although he was not yet openly hostile to Athens, he also was afraid of the long-standing differences between himself and the Athenians, and above all he was anxious to reduce Arrhabaeus, the king of the Lyncestians.

A further circumstance which rendered it easier for them to procure an army from the Peloponnesus was the evil fortune which at the present time attended the Lacedaemonians.