Strabo, Geography

Now for twenty¹ years the Achaeans continued to have a general secretary and two generals, elected annually; and with them a common council was convened at one place (it was called Amarium),² in which these, as did the Ionians before them, dealt with affairs of common interest; then they decided to elect only one general. And when Aratus was general he took the Acrocorinthus away from Antigonus³ and added the city of Corinth to the Achaean League, just as he had added his native city; and he also took over the Megarians; and breaking up the tyrannies in the several cities he made the peoples who were thus set free members of the Achaean League. And he set the Peloponnesus free from its tyrannies, so that Argos, Hermion, Phlius, and Megalopolis, the largest city in Arcadia, were added to the League; and it was at this time that the League reached the height of its power. It was the time when the Romans, after their expulsion of the Carthaginians from Sicily,⁴ made their expedition against the Galatae⁵ who lived in the region of the Padus River. But although the Achaean League persisted rather firmly until the time of the generalship of Philopoemen, yet it was gradually dissolved, since by this time the Romans were in possession of the whole of Greece, and they did not deal with the several states in the same way, but wished to preserve some and to destroy others. Then he⁶ tells the cause of his enlarging upon the subject of the Achaeans, saying that, although they increased in power to the point of surpassing even the Lacedaemonians, they are not as well known as they deserve to be.