The Spartans were drawn up together with their allies. Epaminondas advanced in an oblique line, sending forward the left wing and keeping back the right; but he then ordered the left wing gradually to withdraw to the left, and thus formed on that wing an immense mass. With this he now made a most vigorous attack upon the right wing of the enemy, where the Spartans themselves were stationed. An ordinary general would have done the contrary, directing his force against the part from which no such powerful resistance was to be expected. Pelopidas conducted the attack, and ordered the mass to advance with immense rapidity. We do not know whether the statement is true, that the Thebans advanced fifty men deep. We have only the testimony of Xenophon, but see no reason for denying it. The troops must have been excellently trained, for notwithstanding the dense mass, they advanced with an alacrity as if they had been light troops, just as at present troops advance in an attack with the bayonet, and not according to the fashion of phalangites, who otherwise advanced with deliberate solemnity. The Spartans made a skilful move: in order not to be outflanked, they turned to the right, intending to throw their cavalry upon the right wing of the Bœotians. But the Bœotians made the attack with such precision and quickness, that being beforehand, they routed the Lacedæmonians and Spartans. There Cleombrotus fell, and the Spartans were as decidedly beaten as they well could be. The army did not indeed disperse, but it was absolutely impossible to find any pretext for saying that they had been victorious at any one point, a matter in which the Greeks were otherwise extremely inventive. It requires the partiality of a Xenophon, to leave it undecided as to whether the Spartans were defeated.[13]
After the battle, they appear to have remained together for a time, but there was no one among them able to undertake the command. Meantime, as a report had reached Sparta, that the Bœotians offered resistance, another Spartan army, under Archidamus, a son of Agesilaus, had marched across the Isthmus, and was now approaching, but found the Spartans already defeated. All he could do was to collect the remains of the defeated army and to return with them. They seem to have effected their retreat under the protection of a truce. The only auxiliaries of the Thebans in the battle of Leuctra, had been the Thessalian troops of prince Jason of Pheræ: one of the phenomena of an age, when the old order of things has disappeared, and new institutions have been formed.
If we believe Diodorus, the battle of Leuctra was the direct punishment for perjury: for Cleombrotus, it is said, had concluded a truce with the Thebans, but on the arrival of reinforcements from Peloponnesus, he broke it. One of the narratives must be untrue, either his or that of Xenophon; if the reinforcements under Archidamus arrived before the battle, Xenophon’s account must necessarily be given up. Cleombrotus may have had the peculiar misfortune, which happens to many a one who has been unsuccessful; all that is bad and disgraceful is attributed to him. What makes us still more inclined to disbelieve the account of Diodorus is, that if Archidamus had been present at the battle, it could not have been said that after the battle the Spartan army was without a commander. Diodorus probably too eagerly caught up an account which throws the blame upon the Spartans; it was invented either by Ephorus or by Callisthenes.
The loss of the Spartans in the battle is very differently stated. According to one account, it amounted to 4000 men, which would include, besides the Lacedæmonians and Spartans, all the other allies; others mention only 1000 slain, which number would comprise the Lacedæmonians only; others again estimate their number at 1700; but this last number is erroneous, as has been correctly observed by Schneider in a note on Xenophon, and arose from a hasty glance at the numbers written in the characters of the Greek alphabet. We may take it for granted that not less than 1000 Lacedæmonians fell in the battle; but whether this number also comprised the Spartans or not, is a question which cannot be answered at all. But it is a fact, that the number of the Spartans was so extremely small, that the strength of the Spartan citizens as a body was completely paralysed by the loss of this battle. At one time there had been 9000 citizens, subsequently they are said to have amounted to 8000, but at this time there cannot have been 1000 real citizens, and at a still later time there were only 700. At Leuctra several hundreds of them fell. The ancient Spartan citizens were certainly not more numerous than the