could hire mercenaries. Only one xenagos was needed for each district, therefore easing the manpower pressure on Sparta, which suffered from a severe demographic decline in the 4th century; xenagoi previously had to be sent to every city member of the League. The ten districts were: Lacedemonia, the territory of Sparta in the southern Peloponnese. Arcadia (south?), one half of the historical region, perhaps centred on Tegea. Populous Arcadia was split in two in order to balance the number of soldiers between districts. Arcadia (north?), the other half, perhaps centered on Mantinea. Elis, the western Peloponnese. Achaea, the northern Peloponnese. Corinth and Megara, located on the Isthmus. Sicyon, Phlius, and the Acte (now the Argolis), the northeastern Peloponnese. Acarnania, in western Greece. Phokis and Lokris, in central Greece. Olynthos and Thrace, which had just been conquered. War against Thebes and end of the League During its hegemony, Sparta adopted a more interventionist policy to preserve its supremacy over Greece. Elis had left the League since 420, but Sparta had to wait until the end of the Peloponnesian War to act on it. c.400, Sparta forced Elis back into the League, but also massively weakened it by giving independence to its periokoi cities of the Akrorians and Triphylians. These cities organised as federal states joined the Peloponnesian League as single units. In 385, Mantinea was disbanded into villages to punish its hegemonic behaviour in Arcadia, where Sparta had always adopted a "divide and rule" policy to prevent its unification. This blatant violation of the autonomy proclaimed during the King's Peace of 387 was bitterly received. The defeat of Sparta against Thebes at Leuktra in 371 BC decisively shook its control of the League members. In Arcadia, the Mantineans were the first to act by reconstituting their city. This time, the other Arcadian cities supported them, even their traditional rival Tegea, where pro-Mantinean democrats took over the pro-Spartan oligarchs. United by their hostility to Sparta, the Arcadians could then create the federal Arcadian League and left the Peloponnesian League. The size of the Peloponnesian League was then further reduced by the Theban liberation of Messenia from Spartan control in 369 BC. The states of the north-eastern Peloponnese, including Corinth, Sicyon and Epidauros, adhered to their Spartan allegiance, but as the war continued in the 360s BC, many joined the Thebans or took a neutral position, though Elis and some of the Arcadian