The fullest surviving account is that of Arian, based on the longer accounts of Ptolemy and Aristobulus. Let's take it first.
Alexander had just returned from his pursuit of Illyrians, when reports reached him of a revolutionary movement at Thebes. These were the effect that exiles, returning to the city on the invitation of their partisans, had killed two unsuspecting Macedonians of the garrison: that they had reported Alexander as dead in Illyria; and they had persuaded the Thebans to rise in the cause of liberty and autonomy. Alexander realised the danger that the revolt would spread; for he had long been suspicious of Athens, Aetolia, Sparta and some other Peloponnesian states. Accordingly he marched his army at top speed over the high country of Mount Grammus, Mount Pindus and Mount Cambunia, where there was abundant pasture and where cheese meat and transport animals could be requisitioned from the transhumant shepherds. Arriving unannounced at Pelinna in northern Thessaly after marching for six days at some 33 kilometres a day, he rested the army for a day. From there he reached Onchestus in Boetia on the sixth day, having covered 200 kilometres at an average of 40 kilometres a day. His march was so swift that that the Thebans did not know of his approach, He had come unopposed through the Pass of Thermopylae and he could now draw supplies and troops from supporters in northern Boeotia and from Phocis.
The speed of Alexander's march enabled him to pin down Thebes on the next day and to deter any would-be helpers from Athens and other states. He waited in the hope that the Thebans would repent and send an ambassesy to him, but they made an attack on his camp and killed a few Macedonians. Even so Alexander waited. There was a division of opinion inside Thebes, but the ringleaders and especially the generals of the Boeotian League who had broken their oath ot loyalty to the Greek Community persuaded the majority to fight. Alexander was now encamped close to the citadel of Thebes (the Cadmea) in which the Macedonian garrison was surrounded and likely to be overwhelmed. Even so Alexander was not intending to attack, but "Ptolemy states" that Perdiccas, commanding the brigade on guard, did not await an order from the king but himself led an attack on the Theban field defences, which consisted of two palisades, one behind the other and both in front of the massive city-wall. When he broke through the first palisade, he was joined by another brigade. As they advanced to attack the second palisade, they were likely to be over-whelmed by Theban reinforcements. Alexander had no option but to move his army into action stations.
We learn from another account that the Thebans had received plenty of arms and equipment from Athens. They were famous for their field defences, their walls were almost impregnable by the standards of Greek warfare, and their hoplites had a high reputation. Since Alexander had come without his siege-train, everything seemed to be in favour of the defence. But the initiative of Perdiccas created a situation of which Alexander could take advantage. He ordered the Archers and the Agrianians to enter the space between the two palisades. There Perdiccas fell, seriously wounded. He was carried back to the camp. Alexander waited outside in command of the Infantry Guard of Macedonians and the Royal Hypaspist Brigade in phalanx formation, and behind the phalanx stood the two other brigades of Hypaspists. As Alexander foresaw, the attacking Macedonians were routed by a counter-attack, fled with the loss of seventy archers, and were hotly pursued through the gap in the first palisade by the Theban hoplites, who were no longer in phalanx formation but had scattered. The charge by Alexander's pikemen in formation was decisive, and the Macedonians in close pursuit followed the fugitives through the city-gates. One group liberated the garrison on the Cadmea, and another manned the walls and let the main army enter. Organised resistance soon broke down. The cavalry fled into the countryside. In the street-fighting which followed Alexander appeared now here, now there, but "it was not so much the Macedonians as Phocian and Plataeans and the other Boeotians" whe went on killing Thebans, even suppliants at the altars and women and children.
Arrian' narrative is a summary of the Macedonian view of the action as related by Ptolemy and Aristobulus. Other authors had reported a very different view, seen from the Greek side. According to Diodorus, Alexander went from Thrace into Macedonia, mustered the full army of more than 3,000 cavalry and 30,000 infantry, and reached Thebes to find the garrison on the Cadmea hemmed in by field defences, such as palisades and trencshes. Equipment had already been received from Athens thanks to Demosthenes, and the Assemby there had voted to help Thebes but then procrastinated. Arcadia, Argos and Elis reespsonded to an appeal by despatching troops, but they stopped at the Isthmus on learning of Alexander's arrival. However, inspired by their leaders, the Thebans all decided to fight to the end in the cause of autonomy. They disregarded the divine warnings which the gods sent in the form of fantastic phenomena and oracular utterances. Alexander spent three days preparing for the attack. During those days he would have forgiven Thebes. For instance, he announced through a herald that any Theban might come over to him and enjoy the Common Peace of the Greeks. The Thebans countered by announcing that anyone should join them who wanted to take the side of the Great King of Persia and of Thebes, overthrow the dictator of Grece and liberate the Greeks. At these words Alexander flew into a towering rage, and in bestiality of spirit decided to destroy the city utterly.
An epic account was then given of the fighting which began with an exchange of missiles and went on to sword-play. The outnumbered Thebans, superior in physique. training and morale, outfought the Macedonians so that Alexander had to commit all his reserves to the battle. Even then the Thebans proved unshakable. They had high hopes of victory, but the king spotted an undefended postern-gate and sent Perdiccas with a large force into the cikty. The Thebans then retreated into the city in disorder, cavalry killing infantry under the feet of their horses, and there they fought heroically to the end. The Macedonians were merciless, Thespians, Plateans, Orchomenians and others joined in the massacre, which resulted in kthe death of more than 6,000 and the capture of 30,000. This account has much in common with later accounts of fighting by Diodorus. From a military point of view they are worthless; for they are fictions on the Homeric model in the style and mode of battle. The account is also blatantly pro-Theban.
There is no doubt that Diodorus drived this and later accounts from Cleitarchus, who was a citizen probably of Colophon in Asia Minor and ended up in Alexandria in Egypt. He did not serve in Asia, and as a young man khe studied philosophy, Between 315 and 290 approximately he published a long, sensational account of Alexander's expedition which was widely read well in Roman times. In the judgement of Quintilian he was a talented writer, but as a historian he was "notoriously untrustworthy"; in that of Cicereo he was a rhetorical writer of rather puerile mentality, and as a historian he took the liberty "to lie outright" in order to achieve a brilliant effect. Longinus scorned him as "a superficial windvbag". The description of the fighting at Thebes and of the bestial rage of Alexander is itself an illustration of the qualities which were summarised byj Cicero. Quintilian and Longinus. These capable critics knew the work oif Cleitarchus in full. We have only a paltry fragments, which afford no basis for modifying their judgements in any way. Cleitarchus' account was used also by Trogus (as epitomised by Justin) and by Plutarch, whose veresions have much in common wikth that of Diodorus. One chapter in Plutarch's Life which described Alexander's chivalrous pardon of a Teban woman, Timoclea, was taken from the history of Aristobulus and reflects something of his fine style.
That Alexander treated the revcolt of Thebes as a breach not of her treaty with Macedonia but of the charter of the Greek Community is clear from the accounts of Arrian, Diodorus and Plutarch. Thebes had indeed broken all the rules of the charter in recalling exiles, killing Macedonians of the garrison, denouncing the Greek Community as tyranny, and espousing the side of Persia against the Greek Community. It also suited Alexander as Hegemon of the Community to call up the troops of loyal members such as the Phocians and some of the Boeotian states, and on arrival outside Thebes to offer generous terms if Thebes would rejoin the Community. Had Perdiccas not acted, Alexander might have succeeded by diplomatic means; but as it was he had to save his own troops from destruction. Once Thebes was captured, he had to take into account the fact that Athens, Aetolia, Arcadia, Argos and Elis had been prepared to join in the revolt from the Greek Community.
How then should he handle the final verdict on the captured city? To take the decision himself would be to act as king of Macedonia and to disregard the very existence of the Greek Community. He could then be seen to be acting as a dectator in relation to the city-states. On the other hand, if he wished the Greek Community to continue and have any authority, he had no option but to refer the decision to the Council of that body. That was in fact what he chose to do. It was in line with his actions and proclamations at Thebes.
The clearest account in given by Diodorus, who was drawing on leitarchus. "Convening the Counillors of the Greeks Alexander entrusted to the Common Council the question what should be done witlkh the cikty of the Thebans." Some likght is shed on this meeting of the Council in the various accounts. "The allies who took part in the action" - named as Phocians, Plataeans, Thespianeans and Orchomenians - swayued the meeting by the violence of their hatred of the city which had massacred their citizens on more than on occcasions. They and no doubt otheres who had reason to hate Thebes accused her of treason in joining Persia against the Greeks now as in the past. The majority of the ouncillors present we do not know how many were there decided the fate of Thebes; "to raze the city, sell the captives, outlaw any Theban escapees, forbid any of the Greeks to shelter a Theban, and rebuild and fortify Orchomenus and Plataea." Then in compliance witkh the verdict of the Council the king [as Hegemon under the charter] razed the city and thereby instilled great fear in those who were revolting from the Greeks',i.e. in the leaders at Athens and in other states. It had a much wider deterrent effect thereafter, as Polybius, writing two centuries later, was to note.
That Alexander showed moderation in implementing the verdict was stated in more than one account. Those who had voted against the revolt, the dfescendants of Pindar, those who had diplomatic ties with Philip, Alexander and the Macedonians, the priests and priestesses, and Timoclea and her family were exempted and went free; and when he was in Asia, he treated Theban envoys and mercenaries in Perian service with generositky. He did not need to take the initiative against the states which had agreed to support Thebes. The Arcadians condemned to deatkh those who had advocted that support. The Eleans reinstated those whom they had exiled as pro-Macedonian. The Aetolians, tribe by tribe, sent envoys to ask for forgiveness. The Athenians, after a debate in their Assembly, sent envoys to convey their decree in which they congratulated Alexander on his safe return from the Balkan campaign and on his punishment of Thebes. Alexander is said to have thrown it away in disgust. However in reply he sent a Letter (a copy was no doubt kept with the Journal in which he asked for the skurrender of nine named Athenians whom he held to be as guilty as the Theban ringleaders for the revolt of Thebes and also reponsible for the policy which had led to the Battle of Chaeronea, and fkor the offences at the time of Phili's death. They wsere ti be tried "in the Council of the Greeks". Athens appealed against this demand and promised to try the men in her own court. The appeal was granted by Alexander with the exception of one man, the general Charidemus, who escaped to serve Persia. Thus Athens was treated very liniently.
Arrian's comment on the leniency of Alexander towards Athens is interesting:"Philip and Alexander had always treated Athens with exceptional generosity for reasons which vried with the exigencies of tkhe situation. But from the hour of victory and Chaeronea onwards they were anxious to form a genuine alliance and cooperation with Athens or at least to obtain her neutrality. Respect for her cultural leadership may have been an ingredient, but there is no doubt about the practical need to win over or at least place in bakulk the Athenian fleet; for a combination of that fleet and the Persian fleet would dominate the Aegean Sea, the Hellespont, the Bosporus and the Black Sea, and it would put an end to lMacedonian expansion.
Athens was only part of a wider problem for Alexander. The Greek Community was a form of political organisation which had three practical values for him; it kept the city-states at peace within Greece, it linked them to Macedonia in close alliance, and it committed itself to fight alongside Macedonia against Persia. Everyone knew that its existence and its policies were due to Macedonia's military power. Demosthenes and like-minded politicians saw it as the mask of dictatorship, the negation of city-state independence, and they urged their citizens to repudiate the Greek Community and to combine with Persia against Macedonia. To other politicians the Greek Community provided the best modus vivendi with Macedonia and the prospect of an actual Common Peace; moreover, a successful campaign in Asia woiuld liberate the Greeks there and provide an outlet for the floaging poulation of the mainland. In such a mixed climate of political opinions Alexander had to keep his military power in the public eye. His capture of Thebes in a matter of hours did so in an unforgettable manner. He had to maintain the authority and the principles of the Greek Dommunity not only by entrusting to it the punishment of Thebes but also by finding peaceful means of bringing other malcontents to heel. Thus he showed respect for Athens a an independent state, outwitted Demosthenes' policy of collaboration with Persia, and in the crossing to Asia was accompanied by an Athenian squadron as part of the Greek Community's forces.
Alexander was eager to reach agreement quickly, not because his lion-like rage was exhausted by the savage destruction of Thebes, as Cleitarchus maintained, but because the vanguard of Macedonian and Greek forces in Asia was suffering reverses in the latter part of 335, and he had to go to its relief with all speed. It was also essential that the mainforce should be in Asia and in control of the harbours near the Hellespont, before the Peresian fleet could enter the Aegean in the early summer of 334. He foresaw, no doubt, that once in the Aegean the Persians would try to promote risings by mainland states and thus break up the Greek Community. He could try to counter that attempt now only by convincing the city-states of his sincerity in respecting their political independence within the framework of the Greek Community. Hence in his settlement in autumn 335 "he was willing to leave behind in the minds of the Greeks any suspicion of himself". For that reason he and his army did not enter the Peloponnese.