History of the Peloponnesian War

In the middle of the next summer, the Lacedaemonians, seeing that the Epidaurians their confederates were tired and that of the rest of the cities of Peloponnesus some had already revolted and others were but in evil terms, and apprehending that if they presented it not the mischief would spread still further, put themselves into the field with all their own forces, both of themselves and their Helotes, to make war against Argos, under the conduct of Agis, the son of Archidamus, their king.

The Tegeats went also with them, and of the rest of Arcadia all that were in the Lacedaemonian league. But the rest of their confederates, both within Peloponnesus and without, were to meet together at Phlius; that is to say, of the Boeotians five thousand men of arms and as many light-armed, five hundred horse, and to every horseman another man on foot, of Corinthians two thousand men of arms, and of the rest more or less as they were; but the Phliasians, because the army was assembled in their own territory, put forth their whole power.

The Argives, having had notice both formerly of the preparation of the Lacedaemonians and afterward of their marching on to join with the rest at Phlius, brought their army likewise into the field. They had with them the aids of the Mantineans and their confederates and three thousand men of arms of the Eleians;

and marching forward, met the Lacedaemonians at Methydrium, a town of Arcadia, each side seizing on a hill. And the Argives prepared to give battle to the Lacedaemonians whilst they were single. But Agis, dislodging his army by night, marched on to Phlius to the rest of the confederates, unseen.

Upon knowledge hereof, the Argives betimes in the morning retired first to Argos and afterwards to the forest of Nemea, by which they thought the Lacedaemonians and their confederates would fall in.

But Agis came not the way which they expected, but with the Lacedaemonians, Arcadians, and Epidaurians, whom he acquainted with his purpose, took another more difficult way to pass and came down into the Argive plains. The Corinthians also, and Pellenians and Phliasians, marched another troublesome way. [Only] the Boeotians, Megareans, and Sicyonians were appointed to come down by the way of the forest of Nemea, in which the Argives were encamped, to the end that if the Argives should turn head against the Lacedaemonians, these might set upon them at the back with their horse.