History of the Peloponnesian War

These were the nations, Greeks and barbarians, that inhabited Sicily. And though it were thus great, yet the Athenians longed very much to send an army against it, out of a desire to bring it all under their subjection, which was the true motive, but as having withal this fair pretext of aiding their kindred and new confederates.

But principally they were instigated to it by the ambassadors of Egesta, who were at Athens and earnestly pressed them thereto. For bordering on the territory of the Selinuntians, they had begun a war about certain things concerning marriage and about a piece of ground that lay doubtfully between them. And the Selinuntians, having leagued themselves with the Syracusians, infested them with war both by sea and by land. Insomuch as the Egestaeans, putting the Athenians in mind of their former league with the Leontines made by Laches, prayed them to send a fleet thither in their aid, alleging, amongst many other things, this as principal: that if the Syracusians, who had driven the Leontines from their seat, should pass without revenge taken on them, and so proceed, by consuming the rest of the allies of the Athenians there, to get the whole power of Sicily into their hands, it would be dangerous lest hereafter some time or other, being Dorians, they should with great forces aid the Dorians for affinity, and being a colony of the Peloponnesians join with the Peloponnesians that sent them out, to pull down the Athenian empire; that it were wisdom, therefore, with those confederates they yet retain, to make head against the Syracusians; and the rather, because for the defraying of the war the Egestaeans would furnish money sufficient of themselves.

Which things when the Athenians had often heard in their assemblies from the mouths of the Egestaean ambassadors and of their advocates and patrons, they decreed to send ambassadors to Egesta to see, first, whether there were in their treasury and temples so much wealth as they said there was, and to bring word in what terms the war stood between that city and the Selinuntians. And ambassadors were sent into Sicily accordingly.