century.42 Ismenias led a group of anti-Spartan political hetairoi, while Leontiades led a group that was eager to cozy up to the Spartans.43 When, therefore, part of the Spartan force being sent to Olynthos was encamped near Thebes, Leontiades approached the Spartan commander, Phoibidas, and offered to betray the Theban akropolis, the Kadmeia, to his forces during the Thesmophoria at Thebes, a festival during which the women took over the akropolis. Phoibidas took the opportunity, and once inside Leontiades approached the Theban council to report it as a fait accompli. He had certainly canvassed for support earlier, because he was immediately supported in the council and had Ismenias arrested as a warmonger. Ismenias’s supporters fled the city in fear for their lives; many went to Athens. Ismenias faced a sham trial, defending himself unsuccessfully against charges of Medism and responsibility for every disturbance in Greece, and was executed.44 Whether Phoibidas had acted on orders from Sparta or not was clearly debated in antiquity.45 What matters for us is that the Spartans chose to hold the Kadmeia once it had been won, ushering in a period the Boiotians described as the time when the Spartan spear was dominant.46
The description is not at all inaccurate, for Thebes continued to be held by a Spartan garrison.47 The impact on the rest of Boiotia is interesting. Plataia, destroyed by the Thebans in 427, was probably restored under Spartan sponsorship after 386 and became resolutely pro-Spartan, along with Thespiai.48 The allegiance of Thespiai also made the Corinthian Gulf port at Kreusis available to the Spartans.49 Spartan control of Boiotia was probably more widespread, managed through puppet governments and garrisons: Xenophon later tells us that they had, in the years prior to 378, established narrow oligarchies in all the poleis, which caused the dēmos in each city to withdraw to Thebes, becoming an unlikely haven for democrats, if not for democracy itself.50 We know also that a pro-Spartan government was in place in Tanagra in 377 and probably had been for some years.51 It appears, then, that the Spartan seizure of Thebes in 382 had wider ramifications for the region than is typically realized; the regional takeover was certainly facilitated by political stasis in the Boiotian poleis. The blow dealt by the Spartans in 382 and facilitated by Theban dissidents resulted in deep fractures to the regional system and its institutions.
In 379 the Spartans and their allies finally took Olynthos and made it a member of the Peloponnesian League.52 Surprisingly, however, the terms of their treaty contain not a single hint that the Spartans required the dismantling of the institutions that bound the Chalkideis together.53 The issue of Sparta remained divisive in Thebes, where there was no similar softening of anticooperative sentiment. In the winter of 379/8 Theban exiles and several malcontents within the pro-Spartan Theban government murdered the polemarchs, described by Xenophon as tyrants, and immediately accomplished the adherence of the Theban hoplites and cavalry.54 The Thebans immediately set about rebuilding the Boiotian koinon, conducting an election of boiotarchs to govern in place of the polemarchs. But the election was held by Thebans, not by all the Boiotians, and those elected were certainly Theban. This fact had profound effects on the nature of the koinon as it developed over the next decade.55 The Spartan garrison on the Kadmeia was expelled with the help of the Athenians and other Boiotians, most of its members being treacherously killed.56 Early in 378 the Spartans sent a force to Boiotia under the new king, Kleombrotos, who found the Plataians and Thespians still willing to help; after an ineffectual stay he left Sphodrias as harmost at Thespiai with a garrison, funds, and an order to hire mercenaries.57 If nothing else Kleombrotos did manage to frighten both the Thebans, who did not relish the prospect of taking on the Spartan army alone, and the Athenians, who had no taste for the Spartan army traversing their territory. It was fear, then, that threw the Athenians and Thebans into alliance.58 When Sphodrias attempted an unauthorized raid on Peiraieus, the Athenians felt their own vulnerability and probably saw that the King’s Peace was now a mere sham.59 Around this time the Athenians established their system of alliances known as the Second Athenian Confederacy; although the system was formalized and an allied synedrion established in spring 377 by the decree of Aristoteles, the recent alliance with Thebes provided a paradigm for the terms on which other states would join.60 Whether this system of alliances was formalized before or after Sphodrias’s attempt on Peiraieus in 378 has been debated.61 The somewhat ominous clause stating that the Athenians should send three ambassadors “to persuade the Thebans of whatever good thing they can” may point to Athenian efforts to stave off the conflict between the Boiotian koinon, now being vigorously rebuilt, and the Spartans over the terms of the King’s Peace.62 According to Xenophon the Athenians now “assisted the Boiotians with great eagerness” (Hell. 5.4.34).
Thespiai continued to be friendly to the Spartans and became a base from which the Spartan army, again under Agesilaos, ravaged the territory of Thebes in the fall of 378 and spring of 377, doing enough damage to cause a grain shortage.63 A third planned invasion, in spring 376, was thwarted by Athenian intervention. As a result, Xenophon reports, “the Thebans marched out boldly against the neighboring poleis and once again took control of them.”64 That process in fact took years. The Spartan garrison was expelled from Orchomenos in 375 by a small Theban force, which then led a victory over the Spartans at Tegyra, just east of Orchomenos.65 Thespiai and Tanagra may have been persuaded to rejoin the koinon, but if that is right then Thespiai had rebelled again by 373, for in this year it was attacked by the Thebans, the city razed to the ground, its extended territory pillaged and depopulated.66 Plataia, which had probably never been reintegrated, suffered the same fate for its stubborn refusal.67
Theban aggression in these years began to alarm the Athenians, who sought in 371 a reaffirmation of the terms of the King’s Peace. They therefore sent an embassy to the Thebans, inviting them to join an embassy to Sparta.68 The Thebans agreed and sent Epameinondas as ambassador.69 Xenophon recounts a series of speeches given by the various Athenian ambassadors, and one of them, Kallistratos, rebukes the Spartans with the charge that as a result of their seizure of the Theban Kadmeia, “all those cities which you so much wanted to be independent are once again under Theban authority.”70 In Plutarch’s version of the story, there was an aggressive confrontation at this conference between Agesilaos and the powerful Theban general Epameinondas, who charged the Spartan king with hypocrisy, arguing that the participation of the Boiotian poleis in a Theban-led koinon was no more a violation of autonomy than the subordination of the perioikic towns of Lakonia to Sparta.71 Xenophon claims that when the allies agreed to renew the common peace and took their oaths, the Thebans did too, in their own name, but on the following day asked to change their oath, so that it would be in the name of all Boiotia. Agesilaos refused and sent orders to Kleombrotos, the Spartan general stationed in Phokis, to invade Boiotia.72 The implication is clear: the Spartans refused to recognize the Boiotian koinon as a state, insisting that it violated the autonomy clause of the King’s Peace. As a result, all sources agree, the Thebans remained outside the peace, and we know of no other Boiotian poleis taking the oath in their own names. Kleombrotos, already in Phokis, could act quickly and launched an invasion of Boiotia, which led to a decisive engagement at Leuktra late in the year 371. The stunning defeat suffered by the Spartans at this battle is one of the major turning points in the history of fourth-century Greece. Leuktra led, undeniably, to a wholly different world, in which the Spartans were badly weakened and the Thebans wildly emboldened.73 That different world is described by modern historians as the Theban hegemony, adopting the language of hēgemonia used by the ancient sources about Thebes’ position vis-à-vis the rest of Greece for the next nine years. Yet this label captures only a part of the story that interests us, for these years also witnessed the burgeoning of formal koinon institutions throughout mainland Greece, a phenomenon that cannot be tied in every case to the energies of the Boiotians’ brilliant statesman Epameinondas.
THEBAN HEGEMONY AND THE HEGEMONY OF THE KOINON, 371–346
The Athenians received Theban news of their victory at Leuktra with obvious distress; the herald was not even offered hospitality, much less a promise of aid.74 Several attempts were made to arbitrate in the dispute between Thebes and Sparta, but the status of the Boiotian and the Lakonian perioikic poleis remained unresolved.75 The Athenians soon took