Immediately following the failure of the peace talks, orders were sent out from Sparta to the Spartan king Cleombrotus, who was at the head of an army in Phocis, commanding him to march directly to Boeotia. Skirting north to avoid mountain passes where the Boeotians were prepared to ambush him, Cleombrotus entered Boeotian territory from an unexpected direction and quickly seized a fort and captured 10 or 12 triremes. Then marching towards Thebes, he camped at Leuctra, in the territory of Thespiae. Here, the Boeotian army came to meet him. The Spartan army contained some 10,000 hoplites, 700 of whom were the elite warriors known as Spartiates. The Boeotians opposite them numbered about 6,000, but were bolstered by a cavalry superior to that of the Peloponnesians.
Epaminondas was given charge of the Boeotian army, with the other six Boeotarchs in an advisory capacity. Pelopidas, meanwhile, was captain of the Sacred Band, the elite Theban troops. Before the battle, there was evidently much debate amongst the Boeotarchs about whether to fight or not. As a consistent advocate of an aggressive policy, Epaminondas wished to fight, and supported by Pelopidas, he managed to swing the vote in favour of battle. During the course of the battle, Epaminondas was to display a grasp of tactics hitherto unseen in Greek warfare.
The phalanx formation used by Greek armies had a distinct tendency to veer to the right during battle, "because fear makes each man do his best to shelter his unarmed side with the shield of the man next him on the right". Traditionally, a phalanx therefore lined up for battle with the elite troops on the right flank to counter this tendency. Thus, in the Spartan phalanx at Leuctra, Cleombrotus and the elite 'Spartiates' were on the right, while the less experienced Peloponnesian allies were on the left. However, needing to counter the Spartans' numerical advantage, Epaminondas implemented two tactical innovations. Firstly, he took the best troops in the army, and arranged them 50 ranks deep (as opposed to the normal 8–12 ranks) on the left wing, opposite Cleombrotus and the Spartans, with Pelopidas and the Sacred Band on the extreme left flank. Secondly, recognizing, that he could not have matched the width of the Peloponnesian phalanx (even before the deepening the left flank), he abandoned all attempts to do so. Instead, placing the weaker troops on the right flank, he "instructed them to avoid battle and withdraw gradually during the enemy's attack". The tactic of the deep phalanx had been anticipated by Pagondas, another Theban general, who used a 25 man deep formation at the Battle of Delium. However, the reversing of the position of the elite troops, and an oblique line of attack were innovations; it seems that Epaminondas was therefore responsible for the military tactic of refusing one's flank.
The fighting at Leuctra opened with a clash between the cavalry, in which the Thebans were victorious over the inferior Spartan cavalry, driving them back into the ranks of the infantry, and thereby disrupting the phalanx. The battle then became general, with the strengthened Theban left flank marching to attack at double speed, while the right flank retreated. After intense fighting, the Spartan right flank began to give way under the impetus of the mass of Thebans, and Cleombrotus was killed. Although the Spartans held on for long enough to rescue the body of the king, their line was soon broken by the sheer force of the Theban assault. The Peloponnesian allies on the left wing, seeing the Spartans put to flight, also broke and ran, and the entire army retreated in disarray. One thousand Peloponnesians were killed, while the Boeotians lost only 300 men. Most importantly, since it constituted a significant proportion of the entire Spartan manpower, 400 of the 700 Spartiates present were killed, a loss that posed a serious threat to Sparta's future war-making abilities. When, after the battle, the Spartans asked if they and the Peloponnesians could collect the dead, Epaminondas suspected that the Spartans would try to cover-up the scale of their losses. He therefore allowed the Peloponnesians to remove their dead first, so that those remaining would be shown to be Spartiates, and emphasise the scale of the Theban victory!
The victory at Leuctra shook the foundations of the Spartan dominance of Greece to the core. Since the number of Spartiates was always relatively small, Sparta had relied on her allies in order to field substantial armies. However, with the defeat at Leuctra, the Peloponnesian allies were less inclined to bow to Spartan demands. Furthermore, with the loss of men at Leuctra and other battles, the Spartans were not in a strong position to reassert their dominance over their erstwhile allies.
For the first time, the Spartans had been defeated by an army smaller than their own. Even worse, it had hardly any soldiers left, and the next decades it was to look for money to buy mercenaries.
In the immediate aftermath of Leuctra, the Thebans considered following up their victory by taking their vengeance on Sparta; they also invited Athens to join them in doing so. However, their Thessalian allies under Jason of Pherae dissuaded them from shattering what remained of the Spartan army. Instead, Epaminondas occupied himself with consolidating the Boeotian confederacy, compelling the previously Spartan-aligned polis of Orchomenus to join the league.
The following year the Thebans invaded the Peloponnesus, aiming to break Spartan power for good. It is not clear exactly when the Thebans started to think not just of ending the Spartan hegemony, but of replacing it with one of their own, but it is clear that eventually this became their aim. Hans Beck asserts that, unlike Sparta in the Peloponnesian League and Athens in the Delian League, Thebes made no effort either to create an empire or to bind its allies in any sort of permanent and stable organization. Indeed, after Leuctra Thebes devoted its attention to diplomatic efforts in Central Greece rather than schemes of domination further afield. By late 370 Thebes' network of alliances in central Greece made her secure in the area—as she had not been before Leuctra—and offered scope for further expansion of Theban influence.
When, in the immediate aftermath of Leuctra, the Thebans had sent a herald to Athens with news of their victory, the messenger was met with stony silence. The Athenians then decided to take advantage of the Spartan discomfiture, holding a conference in Athens, in which the peace terms proposed earlier in 371 BC were ratified by all cities (except Elis); and this time, the treaty explicitly made the Peloponnesian cities, formerly under Spartan dominance, independent. Taking advantage of this, the Mantineans decided to unify their settlements into a single city, and to fortify it; a decision which greatly angered Agesilaus. Furthermore, Tegea, supported by Mantinea, instigated the formation of an Arcadian alliance. This led to the Spartans declaring war on Mantinea, whereupon the majority of Arcadian cities grouped together to oppose the Spartans (thus forming the confederation that the Spartans were trying to prevent), and requested assistance from the Thebans. The Theban force arrived late in 370 BC, and it was led by Epaminondas and Pelopidas, both at this time Boeotarchs. As they journeyed into Arcadia, the Thebans were joined by armed contingents from many of Sparta's former allies, swelling their forces to some 50–70,000 men. In Arcadia Epaminondas encouraged the Arcadians to form their proposed league, and to build the new city of Megalopolis (as a center of power opposed to Sparta).
Epaminondas, supported by Pelopidas and the Arcadians, then persuaded the other Boeotarchs to invade Laconia itself. Moving south, they crossed the Evrotas River, the frontier of Sparta, which no hostile army had breached in memory. The Spartans, unwilling to engage the massive army in battle, simply defended their city, which the Thebans did not attempt to capture. The Thebans and their allies ravaged Laconia, down to the port of Gythium, freeing some of the Lacedaemonian perioeci from their allegiance to Sparta. Epaminondas briefly returned to Arcadia, before marching south again, this time to Messenia, a region which the Spartans had conquered some 200 years before. Epaminondas freed the helots of Messenia, and rebuilt the ancient city of Messene on Mount Ithome, with fortifications that were among the strongest in Greece. He then issued a call to Messenian exiles all over Greece to return and rebuild their homeland. The loss of Messenia was particularly damaging to the Spartans, since the territory comprised one-third of Sparta's territory and contained half of their helot population. The helots' labor allowed the Spartans to become a "full-time" army.
Epaminondas' campaign of 370/369 has been described as an example of "the grand strategy of indirect approach", which was aimed at severing "the economic roots of her [Sparta's] military supremacy." In mere months, Epaminondas had created two new enemy states that opposed Sparta, shaken the foundations of Sparta's economy, and all but devastated Sparta's prestige. This accomplished, he led his army back home, victorious.
In order to accomplish all that he wished in the Peloponnesus, Epaminondas had persuaded his fellow Boeotarchs to remain in the field for several months after their term of office had expired. Upon his return home, Epaminondas was therefore greeted not with a hero's welcome but with a trial arranged by his political enemies. According to Cornelius Nepos, in his defense Epaminondas merely requested that, if he be executed, the inscription regarding the verdict read:
Epaminondas was punished by the Thebans with death, because he obliged them to overthrow the Lacedaemonians at Leuctra, whom, before he was general, none of the Boeotians durst look upon in the field, and because he not only, by one battle, rescued Thebes from destruction, but also secured liberty for all Greece, and brought the power of both people to such a condition, that the Thebans attacked Sparta, and the Lacedaemonians were content if they could save their lives; nor did he cease to prosecute the war, till, after settling Messene, he shut up Sparta with a close siege.
The jury broke into laughter, the charges were dropped, and Epaminondas was re-elected as Boeotarch for the next year!
In 369 BC the Argives, Eleans and the Arcadians, eager to continue their war against Sparta, recalled the Thebans to their support. Epaminondas, at the height of his prestige, again commanded an allied invasion force. Arriving at the Isthmus of Corinth, the Thebans found it heavily guarded by the Spartans and Athenians (along with the Corinthians, Megarans and Pellenians). Epaminondas decided to attack the weakest spot, guarded by the Lacedaemonians; in a dawn attack he forced his way through the Spartan position, and joined his Peloponnesian allies. The Thebans thus won an easy victory and crossed the Isthmus. Diodorus stresses that this was "a feat no whit inferior to his former mighty deeds".
However, the rest of the expedition achieved little: Sicyon and Pellene became allied to Thebes, and the countryside of Troezen and Epidaurus was ravaged, but the cities could not be taken. After an abortive attack on Corinth and the arrival of a task force sent by Dionysius of Syracuse to aid Sparta, the Thebans decided to march home.
When Epaminondas returned to Thebes, he continued to be dogged by his political enemies who prosecuted him for the second time. They actually succeeded in excluding him from the office of Boeotarch for the year 368 BC. This was the only time from the Battle of Leuctra until his death that he did not serve as Boeotarch. In 368, the Theban army marched into Thessaly to rescue Pelopidas and Ismenias, who had been imprisoned by Alexander of Pherae while serving as ambassadors. The Theban force not only failed to overcome Alexander and his allies, but got into serious difficulties, when it tried to withdraw; Epaminondas, serving as a private soldier, succeeded in extricating it. In early 367, Epaminondas led a second Theban expedition to free Pelopidas, and Ismenias. He finally outmaneuvered the Thessalians, and secured the release of the two Theban ambassadors without a fight.
In the spring of 367 BC, Epaminondas again invaded the Peloponnesus. This time an Argive army captured part of the Isthmus on Epaminondas's request, allowing the Theban army to enter the Peloponnesus unhindered. On this occasion, Epaminondas marched to Achaea, seeking to secure their allegiance to Thebes. No army dared to challenge him in the field, and the Achaean oligarchies therefore acquiesced to the request that they to be allied to Thebes. Epaminondas' acceptance of the Achaean oligarchies roused protests by both the Arcadians and his political rivals, and his settlement was thus shortly reversed: democracies were set up, and the oligarchs exiled. These democratic governments were short-lived, since the pro-Spartan aristocrats from all the cities banded together and attacked each city in turn, re-establishing the oligarchies. According to G.L. Cawkwell, "the sequel perhaps showed the good sense of Epaminondas. When these exiles recovered the cities, they 'no longer took a middle course'." In the light of their treatment by Thebes, they abandoned their previously neutral stance, and thereafter "fought zealously in support of the Lacedaemonians".
In 366/365 BC an attempt was made to make a common peace, with the Persian King Artaxerxes II as arbiter and guarantor. Thebes organized a conference to have the terms of the peace accepted, but their diplomatic initiative failed: the negotiations could not resolve the hostility between Thebes and other states that resented its influence (such as the Arcadian leader Lycomedes who challenged the right of the Thebans to hold the congress in Thebes); the peace was never fully accepted, and fighting soon resumed.
Throughout the decade after the Battle of Leuctra, numerous former allies of Thebes defected to the Spartan alliance or even to alliances with other hostile states. By the middle of the next decade, even some Arcadians (whose league Epaminondas had helped establish in 369 BC) had turned against them. At the same time, however, Epaminondas managed through a series of diplomatic efforts to dismantle the Peloponnesian league: the remaining members of the league finally abandoned Sparta (in 365 Corinth, Epidaurus, and Phlius made peace with Thebes and Argos), and Messenia remained independent and firmly loyal to Thebes.
Boeotian armies campaigned across Greece as opponents rose up on all sides; Epaminondas even led his state in a challenge to Athens at sea. The Theban demos voted him a fleet of a hundred triremes to win over the Rhodes, Chios, and Byzantium. The fleet finally sailed in 364, but modern scholars believe that Epaminondas achieved no lasting gains for Thebes on this voyage. In that same year, Pelopidas was killed while campaigning against Alexander of Pherae in Thessaly. His loss deprived Epaminondas of his greatest Theban political ally.
In the face of this increasing opposition to Theban dominance, Epaminondas launched his final expedition into the Peloponnese in 362 BC. The immediate goal of the expedition was to subdue Mantinea, which had been opposing Theban influence in the region. Epaminondas brought an army drawn from Boeotia, Thessaly and Euboea. He was joined by Tegea, which was the center of local opposition to Mantinea, Argos, Messenia, and some of the Arcadians. Mantinea, on the other hand, had requested assistance from Sparta, Athens, Achaea and the rest of Arcadia, so that almost all of Greece was represented on one side or the other.
This time the mere presence of the Theban army was not enough to cow the opposition. Since time was passing and the Mantinean alliance showed no signs of capsizing, Epaminondas decided that he would have to break the stalemate. Hearing that a large Lacedaemonian force was marching to Mantinea, and that Sparta was practically undefended, he planned an audacious night-time march on Sparta itself. However, the Spartan king Archidamus was alerted to this move by an informant, probably a Cretan runner, and Epaminondas arrived to find the city well-defended. Although he did attack the city, he seems to have drawn off relatively quickly on discovering that he had not, after all, surprised the Spartans. Furthermore, the Lacedaemonian and Mantinean troops which had been stationed at Mantinea had marched to Sparta during the course of the day, and dissuaded Epaminondas from attacking again. Now hoping that his adversaries had left Mantinea defenseless in their haste to protect Sparta, Epaminondas counter marched his troops back to his base at Tegea, and then dispatched his cavalry to Mantinea. However, a clash outside the walls of Mantinea with Athenian cavalry foiled this strategy as well. Realising that the time alloted for the campaign was drawing to a close, and reasoning that if he departed without defeating the enemies of Tegea, Theban influence in the Peloponnesus would be destroyed, he decided to stake everything on a pitched battle.
What followed on the plain in front of Mantinea was the largest hoplite battle in Greek history!Epaminondas had the larger army, 30,000 strong infantry and 3,000 cavalry, whilst his opponents numbered 20,000 infantry and 2,000 cavalry. Xenophon says that, having decided to fight, Epaminondas arranged the army into battle order, and then marched it in a column parallel to the Mantinean lines, so that it appeared that the army was marching elsewhere, and would not fight that day. Having reached a certain point in the march, he then had the army down arms, so it appeared they getting ready to camp. Xenophon suggests that "by so doing he caused among most of the enemy a relaxation of their mental readiness for fighting, and likewise a relaxation of their readiness as regards their array for battle". The whole column, which had been marching right-to-left past the front of the Mantinean army then 'right-faced', so that they were now in a battle line, facing the Mantineans. Epaminondas, who had been at the head of the column (now the left wing), brought some companies of infantry from the extreme right wing, behind the battle line, to reinforce the left wing. By this, he recreated the strengthened left-wing that the Thebes had fielded at Leuctra (this time probably made up by all the Boeotians, and not just the Thebes as at Leuctra). On the wings he placed strong forces of cavalry strengthened by light-infantry.
Epaminondas then gave the order to advance, catching the enemy off guard, and causing a furious scramble in the Mantinean camp to prepare for battle. The battle unfolded as Epaminondas had planned. The cavalry forces on the wings drove back the Athenian and Mantinean cavalry opposite them. Diodorus says that the Athenian cavalry on the Mantinean right wing, although not inferior in quality, could not withstand the missiles from the light-troops that Epaminondas had placed among the Theban cavalry. Meanwhile, the Theban infantry advanced. Xenophon evocatively describes Epaminondas's thinking: "[he] led forward his army prow on, like a trireme, believing that if he could strike and cut through anywhere, he would destroy the entire army of his adversaries." As at Leuctra, the weakened right wing was ordered to hold back and avoid fighting. In the clash of infantry, the issue briefly hung in the balance, but then the Theban left-wing broke through the Spartans line, and the entire enemy phalanx was put to flight. However, at the height of the battle, Epaminondas was mortally wounded by a Spartan, and died shortly thereafter. Following his death, the Thebes and allies made no effort to pursue the fleeing enemy; a testament to Epaminondas's centrality to the war effort!
Xenophon, who ends his history with the battle of Mantinea, says of the battle's results:
When these things had taken place, the opposite of what all men believed would happen was brought to pass. For since well-nigh all the people of Greece had come together and formed themselves in opposing lines, there was no one who did not suppose that if a battle were fought, those who proved victorious would be the rulers and those who were defeated would be their subjects; but the deity so ordered it that both parties set up a trophy as though victorious and neither tried to hinder those who set them up, that both gave back the dead under a truce as though victorious, and both received back their dead under a truce as though defeated, and that while each party claimed to be victorious, neither was found to be any better off, as regards either additional territory, or city, or sway, than before the battle took place; but there was even more confusion and disorder in Greece after the battle than before.
While pressing forward with the troops at Mantinea, Epaminondas was hit in the chest by a spear. Cornelius Nepos suggests the Spartans were deliberately aiming at Epaminondas in the hope of killing him, and thereby demoralizing the Thebans. The spear broke, leaving the iron point in his body, and Epaminondas collapsed. The Thebans around him fought desperately to stop the Spartans taking possession of his body. When he was carried back to camp still living, he asked which side was victorious. When he was told that the Boeotians had won, he said "It is time to die." Diodorus suggests that one of his friends exclaimed "You die childless, Epaminondas" and then burst into tears. To this Epaminondas is supposed to have replied "No, by Zeus, on the contrary I leave behind two daughters, Leuctra and Mantinea, my victories." Cornelius Nepos, whose story is otherwise similar has the last words of Epaminondas as "I have lived long enough; for I die unconquered." When the spear point was withdrawn, Epaminondas quickly expired. In accordance with Greek custom, he was buried on the battlefield.
In matters of character, Epaminondas was above reproach in the eyes of the ancient historians who recorded his deeds. Contemporaries praised him for disdaining material wealth, sharing what he had with his friends, and refusing bribes. One of the last heirs of the Pythagorean tradition, he appears to have lived a simple and ascetic lifestyle even when his leadership had raised him to a position at the head of all Greece. Cornelius Nepos notes his incorruptibility, describing his rejection of a Persian ambassador who came to him with a bribe. These aspects of his character contributed greatly to his renown after his death.
Epaminondas never married and as such was subject to criticism from countrymen who believed he was duty-bound to provide the country with the benefit of sons as great as himself. In response, Epaminondas said that his victory at Leuctra was a daughter destined to live forever.
Extant biographies of Epaminondas universally describe him as one of the most talented generals ever produced by the Greek city-states. Even Xenophon, who fails to note his presence at Leuctra, says of his Mantinean campaign: "Now I for my part could not say that his campaign proved fortunate; yet of all possible deeds of forethought and daring the man seems to me to have left not one undone." Diodorus is effusive in his praise for Epaminondas's military record:
"For it seems to me that he surpassed his contemporaries...in skill and experience in the art of war. For among the generation of Epaminondas were famous men: Pelopidas the Theban, Timotheus and Conon, also Chabrias and Iphicrates...Agesilaus the Spartan, who belonged to a slightly older generation. Still earlier than these, in the times of the Medes and Persians, there were Solon, Themistocles, Miltiades, and Cimon, Myronides, and Pericles and certain others in Athens, and in Sicily Gelon, son of Deinomenes, and still others. All the same, if you should compare the qualities of these with the generalship and reputation of Epaminondas, you would find the qualities possessed by Epaminondas far superior".
As a tactician, Epaminondas stands above every other general in Greek history (unless the Macedonian kings Philip II and Alexander the Great are included), although modern historians have questioned his larger strategic vision. According to Richard A. Gabriel, his tactics "marked the beginning of the end of traditional Greek methods of war". His innovative strategy at Leuctra allowed him to defeat the vaunted Spartan phalanx with a smaller force, and his decision to refuse his left flank was the first recorded instance of such a tactic. Many of the tactical innovations that Epaminondas implemented would also be used by Philip of Macedon, who in his youth spent time as a hostage in Thebes and may have learned directly from Epaminondas himself.
In some ways Epaminondas dramatically altered the face of Greece during the 10 years in which he was the central figure of Greek politics. By the time of his death, Sparta had been humbled, Messenia freed, and the Peloponnese completely reorganized. In another respect, however, he left behind a Greece no different than that which he had found; the bitter divides and animosities that had poisoned international relations in Greece for over a century remained as deep as or deeper than they had been before Leuctra. The brutal internecine warfare that had characterized the years from 432 BC onwards continued unabated until all the states involved were subjugated by Macedon.
At Mantinea, Thebes had faced down the combined forces of the greatest states of Greece, but the victory brought it no spoils. With Epaminondas removed from the scene, the Thebans returned to their more traditional defensive policy, and within a few years, Athens had replaced them at the pinnacle of the Greek political system. No Greek state ever again reduced Boeotia to the subjection it had known during the Spartan hegemony, but Theban influence faded quickly in the rest of Greece. Finally, at Chaeronea in 338 BC, the combined forces of Thebes and Athens, driven into each others' arms for a desperate last stand against Philip of Macedon, were crushingly defeated, and Theban independence was put to an end. Three years later, heartened by a false rumor that Alexander the Great had been assassinated, the Thebans revolted; Alexander squashed the revolt, then destroyed the city, slaughtering or enslaving all its citizens. A mere 27 years after the death of the man who had made it preeminent throughout Greece, Thebes was wiped from the face of the Earth, its 1,000-year history ended in the space of a few days!
Epaminondas, therefore, is remembered both as a liberator and a destroyer. He was celebrated throughout the ancient Greek and Roman worlds as one of the greatest men of history. Cicero eulogized him as "the first man, in my judgement, of Greece," and Pausanias records an honorary poem from his tomb:
By my counsels was Sparta shorn of her glory,
And holy Messene received at last her children.
By the arms of Thebes was Megalopolis encircled with walls,
And all Greece won independence and freedom.
Epaminondas's actions were certainly welcomed by the Messenians and others whom he assisted in his campaigns against the Spartans. Those same Spartans, however, had been at the center of resistance to the Persian invasions of the 5th century BC, and their absence was sorely felt at Chaeronea; the endless warfare in which Epaminondas played a central role weakened the cities of Greece until they could no longer hold their own against their neighbors to the north. As Epaminondas campaigned to secure freedom for the Boeotians and others throughout Greece, he brought closer the day when all of Greece would be subjugated by an invader. Victor Davis Hanson has suggested that Epaminondas may have planned for a united Greece composed of regional democratic federations, but even if this assertion is correct, no such plan was ever implemented. Simon Hornblower asserts that Thebes' great legacy to fourth century and Hellenistic Greece was federalism, "a kind of alternative to imperialism, a way of achieving unity without force", which "embodies a representative principle".
For all his noble qualities, Epaminondas was unable to transcend the Greek city-state system, with its endemic rivalry and warfare, and thus left Greece more war-ravaged but no less divided than he found it. Hornblower asserts that "it is a sign of Epaminondas political failure, even before the battle of Mantinea, that his Peloponnesian allies fought to reject Sparta rather than because of the positive attractions of Thebes". On the other hand, Cawkwell concludes that "Epaminondas must be judged not in relation to these inevitable limitations of Boeotian power. To have established the power of Boeotia and ended the Spartan domination of the Peloponnese was the most and the best that a Boeotian could have done."
