Diodorus of Sicily: Greek historian, author of the Library of World History. His activities can be dated between 60 and 30 BCE.
In October 336, king Philip of Macedonia was killed in the theater of Aegae by Pausanias, one of his bodyguards, and his son Alexander became king. Immediately, the Greek towns wanted to get rid of the Macedonian domination, but Alexander was able to prevent this in the winter. In 335, he campaigned in Thrace and Illyria.
Late in the summer, a false report about Alexander's death made the Thebans revolt against the Macedonian garrison that had after the #Battle of Chaeronea (338) been placed in the Cadmeia, the citadel of Thebes. Alexander marched to the south and stormed the lower city.
The Greek author Diodorus of Sicily, describes what happened in section 17.11.1-14.1 of his World history. The translation is by C. Bradford Welles.
The sack of Thebes
[17.11.1] Now the king in the course of only three days made everything ready for the assault. He divided his forces into three parts and ordered one to attack the palisades which had been erected before the city, the second to face the Theban battle line, and the third as a reserve to support any hard pressed unit of his forces and to enter the battle in its turn.
[17.11.2] For their part, the Thebans stationed the cavalry within the palisades, assigned their enfranchised slaves, along with refugees and resident aliens, to face those who drove at the walls, and themselves made ready to fight before the city with the Macedonian force [...], which was many times their number.
[17.11.3] Their children and wives flocked to the temples and implored the gods to rescue the city from its dangers.
When the Macedonians approached and each division encountered the opposing force of Thebans, the trumpets blew the call to arms and the troops on both sides raised the battle cry in unison and hurled their missiles at the enemy.
[17.11.4] These were soon expended and all turned to the use of the sword at close quarters, and a mighty struggle ensued.
[A description of the fight is included.]
[17.12.1] At length Alexander saw that the Thebans were still fighting unflinchingly for their freedom, but that his Macedonians were wearying in the battle, and ordered his reserve division to enter the struggle. As this suddenly struck the tired Thebans, it bore heavily against them and killed many.
[17.12.2] Still the Thebans did not concede the victory, but on the contrary, inspired by the will to win, despised all dangers. They had the courage to shout that the Macedonians now openly confessed to being their inferiors. Under normal circumstances, when an enemy attacks in relays, it is usual for soldiers to fear the fresh strength of the reinforcements, but the Thebans alone then faced their dangers ever more boldly, as the enemy sent against them new troops for those whose strength flagged with weariness.
[17.12.3] So the Theban spirit proved unshakable here, but the king took note of a postern gate that had been deserted by its guards and hurried Perdiccas with a large detachment of troops to seize it and penetrate into the city.note[In his history of Alexander's reign, Ptolemy wrote that this assault had not been planned, but was due to lack of discipline: Perdiccas' men broke the official line of command. This is probably an invective. After all, Ptolemy and Perdiccas were enemies in 320.]
[17.12.4] He quickly carried out the order and the Macedonians slipped through the gate into the city, while the Thebans, having worn down the first assault wave of the Macedonians, stoutly faced the second and still had high hopes of victory.
When they knew that a section of the city had been taken, however, they began immediately to withdraw within the walls,
[17.12.5] but in this operation their cavalry galloped along with the infantry into the city and trampled upon and killed many of their own men; they themselves rode into the city in disorder and, encountering a maze of narrow alleys and trenches, lost their footing and fell and were killed by their own weapons. At the same time the Macedonian garrison in the Cadmeianote[This garrison had been sent to Thebes by king Philip, in 338.] burst out of the citadel, engaged the Thebans, and attacking them in their confusion made a great slaughter among them.
[17.13.1] So while the city was being taken, many and varied were the scenes of destruction within the walls. Enraged by the arrogance of the Theban proclamation, the Macedonians pressed upon them more furiously than is usual in war, and shrieking curses flung themselves on the wretched people, slaying all whom they met without sparing any.
[17.13.2] The Thebans, for their part, clinging desperately to their forlorn hope of victory, counted their lives as nothing and when they met a foeman, grappled with him and drew his blows upon themselves. In the capture of the city, no Theban was seen begging the Macedonians to spare his life, nor did they in ignoble fashion fall and cling to the knees of their conqueror
[17.13.3] But neither did the agony of courage elicit pity from the foe nor did the day's length suffice for the cruelty of their vengeance. All the city was pillaged. Everywhere boys and girls were dragged into captivity as they wailed piteously the names of their mothers.
In sum, households were seized with all their members, and the city's enslavement was complete.
[17.13.4] Of the men who remained, some, wounded and dying, grappled with the foe and were slain themselves as they destroyed their enemy; others, supported only by a shattered spear, went to meet their assailants and, in their supreme struggle, held freedom dearer than life.
[17.13.5] As the slaughter mounted and every corner of the city was piled high with corpses, no one could have failed to pity the plight of the unfortunates. For even Greeks - Thespians, Plataeans and Orchomenians and some others hostile to the Thebans who had joined the king in the campaign - invaded the city along with him and now demonstrated their own hatred amid the calamities of the unfortunate victims.
[17.13.6] So it was that many terrible things befell the city. Greeks were mercilessly slain by Greeks, relatives were butchered by their own relatives, and even a common dialect induced no pity. In the end, when night finally intervened, the houses had been plundered and children and women and aged persons who had fled into the temples were torn from sanctuary and subjected to outrage without limit.
[17.14.1a] Over six thousand Thebans perished, more than thirty thousand were captured, and the amount of property plundered was unbelievable.
The king gave burial to the Macedonian dead, more than five hundred in number.