History of the Peloponnesian War

The ambassadors were also directed to say that the Athenians, had they wished to play false, might already have made alliance with the Argives, who were indeed come to Athens for that very purpose, and went off furnished with instructions as to any other complaints that the Athenians had to make.

Having reached Lacedaemon they communicated their instructions, and concluded by telling the Lacedaemonians that unless they gave up their alliance with the Boeotians, in the event of their not acceding to the treaty, the Athenians for their part would ally themselves with the Argives and their friends. The Lacedaemonians, however, refused to give up the Boeotian alliance—the party of Xenares the Ephor, and such as shared their view, carrying the day upon this point—but renewed the oaths at the request of Nicias, who feared to return without having accomplished anything and to be disgraced; as was indeed his fate, he being held the author of the treaty with Lacedaemon.

When he returned, and the Athenians heard that nothing had been done at Lacedaemon, they flew into a passion, and deciding that faith had not been kept with them, took advantage of the presence of the Argives and their allies, who had been introduced by Alcibiades, and made a treaty and alliance with them upon the terms following:—