The Battle of Leuctra (Ancient Greek: Λεῦκτρα, Ancient Greek: [lêu̯k.tra]) was fought on 6 July 371 BC between the Boeotians led by the Thebans, and the Spartans along with their allies. The battle occurred in the context of the King's Peace, or Peace of Antalcidas, which had ended the Corinthian War in 386 BC. The Peace was formally renewed in 375 BC, but a disagreement between the Spartans and the Thebans over the protocol for renewing the Peace again in 371 led directly to the battle, which took place in the vicinity of Leuctra, a village in Boeotia in the territory of Thespiae. The mainly Theban victory shattered Sparta's immense influence over the Greek peninsula, and the wider Aegean Greek world, which Sparta had gained with its victory in the Peloponnesian War a generation earlier.
Prelude
The Corinthian War, between Sparta and a Persian-backed coalition of Thebes, Athens, Corinth, Argos and other Greek allies, had ended in 387/6 BC with the King's Peace (also called the Peace of Antalcidas, or the first Common Peace), under the terms of which the autonomy of all Greek cities not under Persian control was guaranteed. Sparta, as the guarantor of the King's Peace in Greece, immediately used this autonomy clause to force the Thebes-dominated Boeotian League to disband. In 382 BC, the Spartan general Phoebidas seized Thebes' acropolis, the Cadmea, thereby assisting the pro-Spartan Leontiades and his oligarchic supporters in taking control of Thebes, a clear violation of Theban autonomy.
In late 379 BC, an anti-Spartan Theban exile faction overthrew Leontiades, and immediately signaled their intent to reconstitute the Boeotian League by electing four of the leaders of their revolt as Boeotarchs, the traditional title of the leaders of the Boeotian League. This resulted in the Boeotian War starting in 378 BC, and Sparta's succession of failed attempts to regain control of Thebes and Boeotia.
A short lived peace, was agreed to again in 375 BC, with renewed aggression by Thebes in 373 BC. Throughout the Boeotian War, Thebes had continued to expand its dominance over Boeotia. It captured and severely damaged the Boeotian towns of both Plataea, long an ally of Athens, and Thespiae, and forced their citizens into exile. By 371 BC, having engaged in costly naval campaigns, both Sparta and Thebes' ally Athens were ready for peace. Thebes, faced with the prospect of fighting Sparta alone, was likewise prepared to agree to a new peace treaty, which, like those of 386 and 375, promised the independence of all Greek cities. When it came time to sign the new treaty, the Theban ambassadors came forward wishing to sign on behalf of the whole Boeotian League, but the Spartans demanded instead that each Boeotian city sign independently, which the Thebans refused.
With Thebes now isolated, Sparta saw an opportunity to reassert its supremacy in central Greece, and the Spartans immediately sent king Cleombrotus I marching, from his position in Phocis in central Greece, into Boeotia. Rather than take the expected and easier route into Boeotia along the northern side of Mount Helicon, the Spartans instead marched over the hills to the south of Helicon, and then proceeded to Leuctra, where they were confronted by a hastily repositioned Boeotian army.
Force sizes and commanders
Several ancient sources give numbers for the sizes of the two armies, but none of these sources gives all the numbers involved, and they nearly all disagree. The general modern consensus is that the Spartan commander King Cleombrotus led approximately 10,000 Peloponnesian infantry, including 700 Spartiates (i.e. full Spartan citizens), and 1,000 cavalry, against 7,000 Boeotian infantry, and 700 cavalry, led overall by the Theban commander Epaminondas, with Pelopidas in command of the elite 300-strong Sacred Band.
According to Xenophon, 700 Spartiates fought at Leuctra, while according to Plutarch, Cleombrotus' Peloponnesian army consisted of 2,000 infantry and 1,000 cavalry.
Diodorus Siculus reports that Epaminondas led a force (which included all Thebans of military age) numbering no more than 6,000, to be joined later by a Thessalian force of 1,500 infantry and 500 cavalry. Other, even later sources give much higher numbers for the Peloponnesians, which are harder to believe. According to Polyaenus, the Peloponnesians numbered 40,000 (against only 6,000 "Thebans"), while Frontinus specifies 24,000 infantry and 1,600 cavalry (against only 3,600 infantry and 400 cavalry). In any case, the similar force ratios (~ 6.5 to 1), given by Polyaenus and Frontinus, are perhaps meant simply to emphasize the difference in the sizes of the two armies.
Order of battle
The normal practice of the ancient Greeks was to establish their heavily armed infantry in a solid rectangular mass, or phalanx, composed of long files, several ranks deep. The number of ranks varied, with eight thought to be a common phalanx depth, though other depths are documented. In order to counter the tendency of the phalanx to drift to the right, Greek commanders traditionally placed their most experienced and highly regarded troops on the right wing, with the entire phalanx usually advancing together.
At Leuctra, Cleombrotus' phalanx consisted of two wings, (according to Xenophon "not more than twelve men deep") with the Spartans on the right, and his allied troops on the left. Cleombrotus himself occupied the traditional king's position between the first and second morai (divisions) of the Spartan wing, accompanied by the Spartan hippeis (an elite infantry force of 300 young men probably in their twenties that constituted the royal bodyguard).
Epaminondas also organized his phalanx into two wings, the Thebans comprising one wing, and the rest of the Boeotians the other. However, in a break from tradition, Epaminondas massed his Theban infantry in a very deep column (according to Xenophon, at least fifty shields deep), placing it on the left, directly opposite Cleombrotus and the Spartan right. The other Boeotians were drawn up in a shallower line, progressively further to the right and rear of the proceeding column, in an echelon formation, facing the Spartan allies. Although the Sacred Band would play a crucial role in the battle, no source reports where (exactly) it was positioned. While not mentioning Leuctra specifically, Plutarch does say that Pelopidas, after the Battle of Tegyra (375 BC), where the Sacred Band had:
fought by themselves and about his own person, never afterwards divided or scattered them, but, treating them as a unit, put them into the forefront of the greatest conflicts.
This has been interpreted to mean that at Leuctra the Sacred Band was deployed as an independent unit somewhere in front. Epaminondas's plan was, apparently, to make the outcome depend solely upon an engagement of the Thebans against the Spartans, by sending his Thebans forward, against the Spartans, and refusing (i.e. holding back) his Boeotian allies. Polyaenus reports that, while rallying his Theban troops:
Epaminondas grasped a large snake, showed it to them, and in front of everyone crushed the animal's head. "You see," he said, "that the rest of the body is useless without the head. In just this way, should we crush this Laconian part, the remaining body of the allies would be useless."
The battle
Accounts of the battle are given by four ancient sources: Xenophon (the only contemporary source), Diodorus Siculus (later first century BC), Plutarch (c. 100 AD), and Pausanias (late second century). The sources are problematic, their accounts are sometimes contradictory, and many particulars of the battle have been the subject of debate among scholars.
Overview
During the battle the massed Theban infantry, with the Sacred Band in front, smashed into the Spartan right wing. They were able to mortally wound the Spartan king Cleombrotus, killing also many of the Spartan hippeis. The Spartan wing was eventually pushed back, then turned, was routed, and fled. According to Xenophon, the "Lacedaemonians" (i.e the Spartans) themselves lost almost 1,000 dead, including about 400 of the 700 Spartiates present. The Boeotian losses were minimal, "about" 300, according to Diodorus Siculus, while Pausanias reports a total of only 47.
Details
Many more details of the battle (sometimes contradictory) are given by the ancient sources. Xenophon's account is the only contemporaneous one, is the most complete, and includes several details not found in any other source. However, rather than being a simple narrative describing what happened, Xenophon's account consists of various reasons (some might say excuses) for the surprising Spartan defeat. Referring to an oracle received by the Thebans saying that the Spartans were destined to be defeated, and other omens portending a Theban victory, Xenophon begins his account of the battle by saying:
Some, to be sure, say that all these things were but devices of the leaders. But in the battle, at any rate, everything turned out adversely for the Lacedaemonians, while for the other side everything went prosperously, even to the gifts of fortune.
According to Xenophon, while both sides were still arming themselves, the Spartans' mercenary peltasts (slingers, javelinieers, and/or light-armed skirmishers) attacked the Boeotian camp followers, baggage handlers, and others who did not wish to fight, as they were attempting to withdraw. This caused these men to flee back into the Boeotian army, inadvertently making it stronger. The battle proper then opened with a cavalry engagement, in which the Spartan cavalry was quickly defeated. Xenophon explains this defeat by saying that, as a result of their recent battles against Orchomenus and Thespiae, the Theban cavalry was more experienced, and that, because the Spartan cavalry was made up of men who did not own their horses and arms, and were the least physically able and ambitious, it was of inferior quality. In any case, the Spartan cavalry fled from the field, back through their own infantry, causing a disruption in the Spartan lines. Moreover, this occurred just as the Thebans were charging into them. At this point Xenophon concludes his account of the action by saying that the Spartan line was able to hold long enough for the mortally wounded Cleombrotus to be carried off the field still alive, but eventually "fell back under the pressure of the Theban mass, while those who were on the left wing of the Lacedaemonians, when they saw that the right wing was being pushed back, gave way." No other sources mention an attack on the withdrawing Boeotians by the Spartans' mercenary peltasts, or give any hint at all of a cavalry engagement. However, Pausanias does say that Epaminondas, suspecting that some of his Boeotian allies, particularly the Thespians, might desert during the battle, declared that all who did not wish to fight could leave, and all the Thespians, and some of the other non-Theban Boeotians did so.
Xenophon makes no mention of Epaminondas, nor says anything about Theban strategies or tactics during the battle, but other sources do. According to Diodorus Siculus, Epaminondas had employed "an unusual disposition of his own", which consisted of an elite wing, where he would be, "intending to fight to the finish with them himself", and ordered his other wing, which he had arranged in "oblique formation", to avoid battle by a gradual withdrawal as they were attacked, hoping to decide the issue by means of his elite wing alone. Diodorus says that then, as the trumpets sounded the charge, both sides attacked simultaneously, with the Spartans attacking in a "crescent formation" (i.e. their left and right advancing faster than their center), and the elite Boeotian wing advancing "double-quick time", while its weaker wing retreated. According to Diodorus, although the Thebans had the advantage in the "valor and the denseness" of their elite line, and many Peloponnesians began to fall (though none had as yet turned to flee), the battle was nevertheless at first evenly fought. But after an "heroic" effort while "sustaining many wounds" Cleombrotus finally fell, and although the Spartans "fighting gallantly about their king" were able to recover his body, they were unable to hold off the "heavy column led by Epaminondas", who were greatly inspired by his "valour and exhortations", and were "with great difficulty" forced back, while still holding formation, but finally "turned and fled in utter rout". Diodorus goes on to describe Leuctra as "a most glorious victory", won "miraculously" by Thebes against the "invincible leaders of Greece".