History of the Peloponnesian War

Now of former achievements, the greatest that was performed was the Median; and yet that had its decision quickly, in two battles by sea and two by land. But of this war both the duration was very long, and sufferings befell Greece in the course of it, such as were never matched in the same time.

For neither were so many cities ever taken and laid desolate, some by barbarians, and some by the parties themselves opposed in the war; (some, too, changed their inhabitants when taken;) nor was there so much banishing of men and bloodshed, partly in the war itself, and partly through sedition.

And things which before were spoken of from hearsay, but scantily confirmed by fact, were rendered not incredible; both about earthquakes, which at once extended over the greatest part of the world, and most violent at the same time; and eclipses of the sun, which happened more frequently than was on record of former times; and great droughts in some parts, and from them famines also; and what hurt them most, and destroyed a considerable part—the plague. For all these things fell upon them at once along with this war:

which the Athenians and Peloponnesians began by breaking the thirty years' truce after the taking of Euboea.

As for the reason why they broke it, I have first narrated their grounds of complaint and their differences, that no one might ever have to inquire from what origin so great a war broke out amongst the Greeks. For the truest reason, though least brought forward in words, I consider to have been, that the Athenians, by becoming great, and causing alarm to the Lacedaemonians, compelled them to proceed to hostilities.

But the following were the grounds of complaints openly alleged on either side, from which they broke the truce, and set to the war.