History of the Peloponnesian War

Meanwhile the Ambraciots from the city arrived at Idomene. Idomene consists of two lofty hills, the highest of which the troops sent on by Demosthenes succeeded in occupying after nightfall, unobserved by the Ambraciots, who had meanwhile ascended the smaller and bivouacked upon it.

After supper Demosthenes set out with the rest of the army, as soon as it was evening; himself with half his force making for the pass, and the remainder going by the Amphilochian hills.

At dawn he fell upon the Ambraciots while they were still abed, ignorant of what had passed, and fully thinking that it was their own countrymen,—

Demosthenes having purposely put the Messenians in front with orders to address them in the Doric dialect, and thus to inspire confidence in the sentinels, who would not be able to see them, as it was still night.