History of the Peloponnesian War

For fourteen years the thirty years' truce which had been concluded after the capture of Euboea remained unbroken; but in the fifteenth year, when Chrysis was in the forty-eighth year of her priesthood[*](The commencement of the war is fixed according to the forms of reckoning customary in the three most important Hellenic states.) at Argos, and Aenesias was ephor at Sparta, and Pythodorus had still four months to serve as archon at Athens, in the sixteenth month after the battle of Potidaea, at the opening of[*](431 B.C.) spring, some Thebans, a little more than three hundred in number, under the command of the Boeotarchs Pythangelus son of Phyleidas and Diemporus son of Onetoridas, about the first watch of the night entered under arms into Plataea, a They had been invited over by some Plataeans, Naucleides and his partisans, who opened the gates for them, intending, with a view to getting power into their hands, to destroy the citizens who were of the opposite party and make over the city to

the Thebans. And they had conducted their intrigue through Eurymachus son of Leontiades, a man of great influence

at Thebes. For, as Plataea was always at variance with them, the Thebans, foreseeing that the war[*](i.e. the war between Athens and Sparta.) was coming, wished to get possession of it while there was still peace and before the war had yet been openly declared. And so they found it easier to make their entry unobserved, because no watch had been set to guard

the city. And when they had grounded their arms in the market-place, instead of following the advice of those who had invited them over, namely to set to work at once and enter the houses of their enemies, they determined rather to try conciliatory proclamations and to bring the city to an amicable agreement. The proclamation made by herald was that, if anyone wished to be an ally according to the hereditary usages of the whole body of the Boeotians, he should take his weapons and join them. For they thought that in this way the city would easily be induced to come over to their side.