Battle of Leuctra and the Theban Hegemony
Thebes destroyed the Spartan army at Leuctra in 371 BC and ended a military reputation of three centuries. Sparta had never lost a pitched battle to a Greek army it outnumbered, and it outnumbered the Thebans by roughly ten thousand to six. Epaminondas did two things nobody had done. Greek phalanxes conventionally advanced with the strongest troops on the right, so that each army's best faced the other's weakest; he put his best on the left, opposite the Spartan king and the Spartiates themselves, and made that wing fifty ranks deep instead of the usual eight. He then advanced obliquely, holding his own weaker right back so that it did not engage until the decision had been taken on the other side. The Sacred Band under Pelopidas, 300 men in pairs, went in first. The Spartan right was broken by weight, the king Cleombrotus was killed, and about 400 of the 700 Spartiates present died. That number is the whole significance. The Spartan citizen body had been shrinking for a century through land concentration and a birth rate nobody could fix, and it could not replace 400 men. Sparta's hegemony ended within two years, when Epaminondas invaded Laconia — the first hostile army to do so in living memory — freed the Messenian helots who had been farming for Spartans for three hundred years, and founded a city for them. Sparta never recovered. Philip of Macedon was a hostage in Thebes during these years and watched Epaminondas and Pelopidas at work. The oblique attack, the deep striking wing and the professional élite unit all turn up in the Macedonian army twenty years later.
- Year: 371 BCE
- Category: Military
