Action against Persia may then have been once again envisaged, but in other respects the precedent of the Delian League was explicitly avoided. There was to be freedom and autonomy for all as well as an allied chamber, or synedrion, that could put motions directly before the Athenian Assembly. An inscription from 372 shows that this chamber had an allied president. In other words, an improvement was intended on the old synod of the Delian League, which met (presumably) only when Athens called it and had no way of influencing policy in an immediate or effective way; for instance, there is no sign of allied influence in Thucydides’ detailed account of the preliminaries to the great Peloponnesian War. The synedrion was to decide on the membership of the confederacy, and it had some financial competence. There was to be joint judicial action: although there would not exactly be a joint court, the synedrion was to participate in treason trials alongside the Athenian Assembly and Council. It is possible (according to recent reinterpretation of the relevant inscriptions) that, within the framework of the confederacy, the Athenians operated an enlightened policy of arbitration and used “foreign judges,” thus anticipating sophisticated Hellenistic methods of settling interstate disputes.
The restrictive policies adopted by Athens are interesting as showing awareness of what had been 5th-century grievances. There was to be no tribute, no governors, no garrisons, and no cleruchies. Land outside Attica was not to be cultivated by Athenians, and “unfavourable stelae” (inscribed pillars) were to be taken down. (Perhaps this is a reference to grants of the right to own land in the empire. It does not seem, however, that much or any land had survived in Athenian hands after the end of the empire in 404, and the importance of this clause may be merely symbolic.) Except for the pledge against private cultivation of land outside Attica, every one of these pledges was to be broken sooner or later, mostly sooner. There is even a hint by an orator of a private Athenian estate on the island of Peparethus, and thus one perhaps should make no exceptions at all.
Athens now began to reorganize its public finances and to build ships. A new system of levying taxes by taxation groups (symmoriai, singular symmoria) was introduced. To make sure there were no cash-flow difficulties, rich individuals were expected to produce money for the state from their own resources and then recoup it from their taxation group. The new Athenian navy defeated Sparta in the battle of Naxos (376), a victory won under the command of the Athenian Chabrias. In western waters another great Athenian commander, Timotheus, won the battle of Alyzia. Those successes produced new members for the confederacy (some states had cautiously stood aloof at first). In Boeotia—which Sparta, under King Agesilaus and initially the other king, Cleombrotus I, repeatedly invaded in the years after the liberation—there was a surprising land defeat of some Spartan contingents at the hands of the Theban Sacred Band, an elite military force composed of 150 pairs of lovers. This, the battle of Tegyra (375), anticipated the more-famous Spartan defeat at Leuctra four years later. The very existence of a Sacred Band was militarily significant, indicating that Spartan professionalism was now being copied by others who would soon overtake Sparta.
By 375 these efforts had exhausted all parties, and they were ready to make peace, or rather to accept another King’s Peace. (Greeks felt uncomfortable about their involvement in this kind of Persian-inspired diplomacy, in which the various peaces were “sent down”—i.e., imposed—by the Persian king. As a result, the Persian aspect to this and other initiatives tends to be minimized or ignored by some literary sources, notably the “Panhellenist” Xenophon.) This time Athens’s improved position was acknowledged in a clause specifically giving it the leadership by sea. Theban expansion
After its expulsion from Thebes, Sparta had steadily lost ground in central Greece. The Thebans energetically centralized Boeotia under their own leadership; for instance, they gained control of Thespiae and—yet again—of the unfortunate Plataea, which must have been resettled at some point, or perhaps just gradually, after the Peloponnesian War. In addition, a new power arose in Thessaly, that of Jason of Pherae, an ally of Thebes and until his assassination in 370 a military despot on the Dionysius model. Sparta was unable to respond to local Thessalian appeals against Jason, proof that Spartan ambition in central Greece had finally come to an end.
Theban expansionism was bound to drive Athens and Sparta together before long. Despite renewed fighting between Athens and Sparta in the west (374 and 373) and despite Thebes’s continued, though increasingly reluctant, contributions to the Athenian navy (373), it was becoming clear that Thebes was the real threat to both Athens and Sparta. In this respect the Second Athenian Confederacy, with its political justification in terms of anti-Spartan sentiment, had already been superseded by events. There were other causes for concern within the confederacy. Tribute by another name had been levied for the western operations of 373, not altogether unreasonably: ships cost money, and Athens did not have great reserves, as it had in the 5th century. Perhaps more disquieting in its implications was the Athenian garrison on Cephallenia, attested by an inscription of 373; there may, however, have been special factors, and it is not known how long the garrison remained.
At a famous peace conference held at Sparta in 371 (which, in fact, resulted in another King’s Peace), Sparta tried to prevent the Thebans from asserting and formalizing their local pretensions by signing on behalf of the whole of Boeotia. After a breach in the negotiations, signaled by a rhetorical duel between Agesilaus and the Theban Epaminondas, “a man famous for culture and philosophy,” as his fellow Boeotian Plutarch described him half a millennium later, the Spartans invaded Boeotia. Twenty days after the peace conference, Sparta was defeated by Thebes on the field of Leuctra, the Theban commander Epaminondas showing more than cultural and philosophical qualities.
That was a major and decisive battle in Greek history. Politically, it was to loosen Sparta’s hold even on its Peloponnesian dependencies and to end its long subjection of Messenia; it introduced a decade of Theban prominence (which was, however, too inconclusive in its results to deserve its usual name of the “Theban hegemony”). Militarily, the battle was innovative in several ways, not only in the sheer professionalism of the Sacred Band. The left wing of the army was deepened to 50 men, in a further development of the Delium arrangement of 424. This provided a flexible “tail,” or reserve force on the left that could be deployed as the course of the battle suggested. The decision about whether, when, and how to deploy it would be the general’s, whose influence on the outcome of the battle was thus greater than had been usual hitherto. By placing the best troops on the left, the Thebans aimed to knock out the best Spartan troops, who were positioned opposite them, occupying the right wing in the traditional hoplite manner. Finally, by marching forward obliquely (rather than straightforwardly, as was customary), the Thebans increased the punch administered by this deepened left.
Perhaps the Spartan defeat needs no explanation other than Theban superiority. The Spartans lost about 1,000 men, 400 of them full Spartan citizens. It is disputed, however, whether manpower problems were the most serious factor in the defeat. Aristotle, on the one hand, explicitly made the connection between the defeat at Leuctra and shortage of men. There were not enough ways for talented or physically vigorous outsiders to acquire Spartan citizenship and too many ways by which full citizens could lose their status. Thus, full citizens might be degraded in status for alleged cowardice in battle, or they might fall into debt through inability to pay their mess bills (these debts often resulted in the takeover of land by women, whose social and economic position was stronger at Sparta than elsewhere). In addition, the number of full citizens was reduced by unavoidable demographic disasters such as the earthquake of 465. On the other hand, it has been replied that non-Spartans (either degraded Spartans, the so-called “inferiors” like Cinadon, or citizens of the surrounding communities) might be and probably were brigaded alongside full Spartans, at least in the 4th century.