Plutarch, Alcibiades
Bernadotte Perrin, Ed.

After this fiasco on the part of the Lacedaemonians Alcibiades was appointed general, and straightway brought the Argives, Mantineans, and Eleans into alliance with Athens.¹ The manner of this achievement of his no one approved, but the effect of it was great. It divided and agitated almost all Peloponnesus; it arrayed against the Lacedaemonians at Mantinea² so many warlike shields upon a single day; it set at farthest remove from Athens the struggle, with all its risks, in which, when the Lacedaemonians conquered, their victory brought them no great advantage, whereas, had they been defeated, the very existence of Sparta would have been at stake. [2]

After this battle of Mantinea, the oligarchs of Argos, ‘The Thousand,’ set out at once to depose the popular party and make the city subject to themselves; and the Lacedaemonians came and deposed the democracy. But the populace took up arms again and got the upper hand.³ Then Alcibiades came and made the people's victory secure. He also persuaded them to run long walls down to the sea, and so to attach their city completely to the naval dominion of Athens. [3] He actually brought carpenters and masons from Athens, and displayed all manner of zeal, thus winning favour and power for himself no less than for his city. In like manner he persuaded the people of Patrae to attach their city to the sea by long walls.⁴ Thereupon some one said to the Patrensians: ‘Athens will swallow you up!’ ‘Perhaps so,’ said Alcibiades, ‘but you will go slowly, and feet first; whereas Sparta will swallow you head first, and at one gulp.’ [4]

However, he counselled the Athenians to assert dominion on land also, and to maintain in very deed the oath regularly propounded to their young warriors in the sanctuary of Agraulus. They take oath that they will regard wheat, barley, the vine, and the olive as the natural boundaries of Attica, and they are thus trained to consider as their own all the habitable and fruitful earth.