Extraordinary as these frequent revolutions appear, they may be easily accounted for by the mode of warfare in those days. Every thing depended on the armies; and these were composed of mercenaries, ever willing to fight against him they had defended the day before, if they fancied his rival to be a more valiant or fortunate leader. Since the death of Alexander, the Macedonian phalanx was no longer dependent on its captains, but they on their men. The impoverishment of the countries, in consequence of war, was such, that the soldier's was almost the only profitable trade; and none prosecuted that trade more ardently than the Gauls, whose services were ever ready for any one who chose to pay for them. 12. After the death of Pyrrhus, Antigonus Gonnatas recovered the Macedonian throne, of which he and his descendants kept uninterrupted possession, yet not till after a violent contest with Alexander, the son and successor of Pyrrhus. But no sooner were they secure from foreign rivals, than the Macedonian policy was again directed against Greece, and the capture of Corinth seemed to insure the dependence of the whole country, when the formation of the Aetolian, and the yet more important Achaean, league, gave rise to relations entirely new, and of the highest interest, even for the universal history of the world. After so many storms, the sun of Greece was about to set in all his splendour! The ancient confederacy of the twelve Achaean cities (see above, p. 145.) had subsisted until the death of Alexander, but was dissolved in the subsequent commotions; particularly when, after the battle of Ipsus, 301, Demetrius and his son made Peloponnesus the principal seat of their power. Some of these cities were now garrisoned by those princes, while in others arose tyrants, generally favourable to their interests. In 281, four asserted their freedom and renewed the ancient federation; which, five years afterwards, was gradually joined by the rest, Antigonus being busied elsewhere, in consequence of his occupation of the Macedonian throne. But the league did not become formidable till the accession of foreign states. This took place, in the first instance, with Sicyon, through the exertions of the liberator of that town, Aratus, who now became the animating spirit of the federation; and in 243 brought over Corinth, after the expulsion of the Macedonian garrison, and Megara. Afterwards the league gradually acquired strength, by the junction of several Grecian cities, Athens among others, 229; and thereby excited the jealousy of the rest. And as Aratus, who was more of a statesman than a general, and possessed but little independence, had in the very outset joined the party of Ptolemy II. the league soon became involved in the disputes of the great powers, and was too often but a mere tool in their hands. The main principles on which it was founded were the following: 1.