=232.= A new confederacy was now formed on the plan of that of Delos, including, in its most prosperous period, seventy cities. Athens was the head, but the independence of the members was carefully guarded. A congress at Athens regulated the share of each in the general expenses. The fortifications of Piræus were completed, new ships of war were built, and all the allies hastened forward their contingents of troops. In Thebes, the Sacred Band was formed—a heavy-armed battalion, consisting of three hundred chosen citizens of the noblest families, bound to each other by ties of the closest friendship. Though Pelopidas was bœotarch, Epaminondas had the most prominent share in the drill and discipline of the troops.
During two summers the army of Agesilaus invaded the country, and carried its depredations to the very gates of Thebes. The third year the Thebans held the passes of Mount Cithæron, and kept out the invaders. The Spartans were no longer successful at sea. They were thoroughly defeated off Naxos by the Athenians, who thus regained their maritime empire in the East; while, in the western seas, Corcyra, Cephallenia, and the neighboring tribes on the mainland joined the Athenian alliance. The Thebans were no less victorious on land. During the two years that they were free from Spartan invasion, most of the Bœotian cities submitted to their control. In 374 B. C., all Spartans were expelled, free governments were restored to every city, except Orchomenus and Chæronea, and the Bœotian League was revived. The Phocians, who had, twenty years before, invited the Spartans into central Greece, were now the objects of vengeance, and not the less because the treasures of Delphi would be the prize of the victor. But Cleombrotus came to the aid of the Phocians, and the aggression was checked.
=233.= The Athenians had now various reasons for enmity against Thebes, and messengers were sent to Sparta with proposals of peace. They were eagerly accepted; but the inopportune restoration of the Zacynthian exiles by Timo´theus, son of Conon, at this crisis, broke off the negotiations, and war was renewed. It was carried on in the western sea, with great expense and no gain to either party; the main object of the Spartans being the conquest of Corcyra, and, of the Athenians, the protection of its independence. At length all parties were weary of war, and a general congress was appointed at Sparta in the spring of 371.