Almost as soon as peace was signed, Sparta and the State of Argos quarrelled. Each wished to get help from Athens, so each sent ambassadors to her. The Argives boldly begged Athens to join them against Sparta; the Spartans were content to remind her that she had signed the Peace of Nicias.
In Athens at this time there was a rich young noble named Alcibiades, who wished the Athenians to make an alliance with the Argives.
But the Spartan ambassadors had already been welcomed by the Athenians, because they had come with full power to arrange fair terms. Alcibiades was as determined as he was angry. To gain what he wished he resolved to play a trick on the Spartan ambassadors. So he went to them in secret, and told them how foolish they had been to tell the Athenians what great powers they had, for the assembly would certainly wrest from them more than they wished to give.
‘When the assembly meets, tell the people,’ said Alcibiades, ‘that you have no power, but that you will send their demands to the Spartan council. I will support you and all will be well, for you will have time to think over their wishes.’
The ambassadors thought that the young noble knew better than they how his countrymen should be treated, and they promised to follow his advice.
So when the assembly met the next day, the Spartans declared that they had come only to report what the Athenians should say, that they had no power to arrange terms until they had heard from their own council.
No sooner had they spoken than Alcibiades jumped to his feet, and to the dismay of the ambassadors he pointed to them with scorn, saying, ‘These men say one thing one day, and another thing the next day; they are not to be trusted. Let us refuse to have anything more to do with them.’
The Athenians at once agreed with Alcibiades that it was useless to treat with such unreliable ambassadors, and they then made an alliance with the Argives.
When the Spartans reached their own country they told how they had been deceived by Alcibiades, and how rudely they had been treated by the assembly. And this, as well as the alliance which the Athenians had made with the Argives, was the cause of the second part of the Peloponnesian War.
The Spartans were thirsting to avenge the battle of Sphacteria, and to wipe out the memory of their surrender. When they met the Athenians in 418 B.C. at Mantinea they fought with the courage and the fierceness that had made them invincible until the fatal day of Sphacteria.