Ancient Greece, Late Classical Period: Theban Hegemony (371-362 BC): Peloponnese

Theban Hegemony (371-362 BC)

In the Amphictyonic Council the Thebans accused Sparta of seizing the Cadmea in time of peace and the Spartans were fined five hundred talents, which was doubled when they did not pay. With Thebes now a greater threat than Sparta, the Athenians seeking to prevent either of them obtaining the supremacy in Greece called upon the other states to form a new coalition under the terms of the Peace of Antalcidas. Except for Elis (and Sparta), all the other Peloponnesian states joined this new alliance and thus became independent of Sparta. But the Acarnanians, Euboeans, Locrians, Malians and Phocians joined the Boeotian Coalition, under the Boeotian League.

Peloponnese: Tearless Battle, Cromnus

Many of the Peloponnesian states now decided to rid themselves once and for all of Spartan domination: Arcadia (especially Mantinea and Tegea), Achaea, Argos, Corinth, Elis and Sicyon, went into stasis (civil war), with anti-Spartan democrats challenging pro-Spartan oligarchs. In 371 BC Mantinea re-synoecised, i.e. the five villages were brought back into a unified state within a rebuilt city wall. The driving force behind this was probably Lycomedes (d.366 BC) who in the following year led the effort to found the Arcadian League, which included most of the city-states in Arcadia. The Eleans, who had lost Triphylia to the Spartans in 398 BC, and the Argives, the traditional enemy of the Spartans, joined with the Arcadian League to form a triple alliance. Expecting a military response from Sparta and after making an unsuccessful appeal to the Athenians to join them, the triple alliance approached the Thebans, who voted to become allies. A Spartan army under Agesilaus was sent to Arcadia to restore the oligarchs, but he achieved nothing and went back to Sparta.

In winter 370/69 BC Epaminondas with the Boeotian army and her allies entered the Peloponnese. He joined forces with the Arcadians, Argives and Eleans then advanced into Laconia to threaten Sparta itself. The city was unwalled and the Spartiates a mere eight hundred in number, but Sparta had received reinforcements from her traditional allies Corinth, Phlius, Epidaurus and Pellene, and Agesilaus had liberated and armed six thousand helots to aid the defence. Epaminondas abandoned his attempt on the city, crossed the Eurotas River and went southwards as far as Helos and Gytheum.

He returned along the Eurotas Valley, crossed to Messenia, freed the helots and fortified Messene at the foot of Mount Ithome. The loss of the rich agricultural Messenian Plain was a devastating blow to the ambitions of the Spartans. Thereafter, to the west Sparta would be faced with hostile Messenia; and to the north the Arcadian League with its new capital, Megalopolis (governed by an assembly of Ten Thousand), near the Spartan border, which Epaminondas had made possible by his weakening of Sparta, would be a constant threat.

Meanwhile, the Spartans had sent to Athens for assistance and the Athenians, anxious over the rising power of Thebes, sent out their entire military force under Iphicrates to help in saving Sparta from destruction. When it was clear that Sparta was safe, Iphicrates, unwilling to face Epaminondas’ veterans in the open, was content to harry the Thebans as they marched home across the Isthmus.

In summer 369 BC Epaminondas returned with an army of seven thousand infantry and six hundred cavalry. In the interim the Spartans and Athenians had put forces in place across the Isthmus. In a surprise attack before dawn he carried the western end of the Isthmus and gained control of the northern Peloponnesian cities of Sicyon and Pellene. Initially he allowed Sicyon to keep its oligarchic government, but later the Thebans gave their support to the Sicyonian leader Euphron, who advocated democracy but once in power became a tyrant (r.368-366 BC). However, the rest of the expedition achieved little. After an abortive attack on Corinth and the arrival of a task force sent by Dionysius of Syracuse to aid Sparta, Epaminondas decided to go home.

After the Thebans departed, the Arcadian League attempted to gain control of the Peloponnese without the assistance of the Thebans. Led by Lycomedes, they rescued Argive troops in Epidaurus where they were in danger of being cut off by a body of Athenians and Corinthians under Chabrias. They then marched against Asine in Messenia, defeated a Spartan commander Geranor, who had drawn out the garrison to oppose them, and destroyed the suburbs of the town. Athens found herself fighting against Arcadia rather than against Boeotia.

In winter 368 BC Philiscus of Abydos, an agent of Ariobarzanes, satrap of Hellespontine Phrygia (r.387-362 BC), called a congress at Delphi to discuss a general peace. The negotiations failed when the Spartans refused to recognize Messenian independence. Philiscus then engaged two thousand mercenaries to help Sparta. This contingent together with a second force of mercenaries sent by Dionysius enabled Sparta in spring 367 BC to win the ‘Tearless Battle’ against the Arcadians in which Sparta is said to have suffered no casualties.

In spring 366 BC Epaminondas returned to the Peloponnese. The Argives had been persuaded to capture the passage past Cenchreae on the Isthmus and the Thebans passed the Spartan blockade without difficulty. Epaminondas marched westwards and persuaded ruling oligarchies of the Achaean cities to become allies of Thebes. The Arcadians and other opponents protested to Thebes about this arrangement, and so the Boeotians expelled the oligarchs and installed democracies in their place. However, when the Thebans returned to Boeotia, the pro-Spartan aristocrats from all the cities banded together, attacked each city in turn and re-established the oligarchies.

In 365 BC the Spartans recaptured Sellasia, lost in the invasion of 370/69 BC, and later in the same year captured Cromnus in Arcadia. This threat to their communications brought a swift response from the Arcadians and their allies, and the Spartan force in Cromnus soon found itself under siege. The Spartans managed to extricate most of their garrison from the town, but lost over a hundred men.