History of the Peloponnesian War

The greatest action before this was that against the Medes; and yet that, by two battles by sea and as many by land, was soon decided. But as for this war, it both lasted long and the harm it did to Greece was such as the like in the like space had never been seen before.

For neither had there ever been so many cities expugned and made desolate, what by the barbarians and what by the Greeks warring on one another (and some cities there were that when they were taken changed their inhabitants), nor so much banishing and slaughter, some by the war some by sedition, as was in this.

And those things which concerning former time there went a fame of, but in fact rarely confirmed, were now made credible: as earthquakes, general to the greatest part of the world and most violent withal; eclipses of the sun oftener than is reported of any former time; great droughts in some places, and thereby famine; and that which did none of the least hurt but destroyed also its part, the plague.

All these evils entered together with this war, which began from the time that the Athenians and Peloponnesians brake the league which immediately after the conquest of Euboea had been concluded between them for thirty years.

The causes why they brake the same and their quarrels I have therefore set down first, because no man should be to seek from what ground so great a war amongst the Grecians could arise.

And the truest quarrel, though least in speech, I conceive to be the growth of the Athenian power, which putting the Lacedaemonians into fear necessitated the war. But the causes of the breach of the league publicly voiced were these.