The part which the Greek cities of Asia took in the expedition of Cyrus involved them in a war with Persia, in which they were aided by the Spartans. Agesila'us entered Asia with a considerable force (396 B.C.), and in the following year he defeated the Persians in a great battle on the plains of Sardis, in Lydia. But in 394 the Spartan king was called home to avert the dangers which threatened his country in a war that had been fomented by the Persian king in order to save his dominions from the ravages of the Spartans. The King of Persia had supplied Athens with a fleet which defeated the Spartan navy at Cni'dus, and Persian gold rebuilt the walls of Athens. A battle soon followed between the Spartans on one side and the Thebans and Athenians on the other, in which the former were defeated and Lysander was slain. On the other hand, Athens and her allies were defeated, in the same year, in the vicinity of Corinth, and on the plains of Corone'a. Finally, after the war had continued eight years, and Sparta had virtually lost her maritime power, the peace of Antal'cidas, as it is called, was concluded with Persia, at the instance of Sparta, and was ratified by all the states engaged in the contest (387 B.C.). By the treaty with Persia, Athens regained three of the islands she had been obliged to relinquish to Sparta under Lysander; but the Greek cities in Asia were given up to Persia, and both Athens and Sparta lost their former allies. It was the unworthy jealousy of the Grecians, which the Persian king knew how to stimulate, that prompted them to give up to a barbarian the free cities of Asia; and this is the darkest shade in the picture. Though Sparta was the most strongly in favor of the terms of the treaty, yet Athens was the greatest gainer, for she once more became an independent and powerful state. It was not long before ambition, and the resentment of past injuries, involved Sparta in new wars. When her thirty years' truce with Mantine'a had expired, she compelled that city, which had formerly been an unwilling ally, to throw down her walls, and dismember her territory into the four or five villages out of which it had been formed. Each of these divisions was now left unfortified, and placed under a separate oligarchical government. Sparta did this under the pretext that the Mantine'ans had supplied one of her enemies with provisions during the preceding war, and had evaded their share of service in the Spartan army. The jealousy of Sparta was next aroused against the rising power of Olynthus, a powerful confederacy in the south-eastern part of Macedonia, which had become engaged in hostilities with some rival cities; and the Spartans readily accepted an invitation of one of the latter to send an army to its aid.