About this time, Demaratus the Corinthian, an old friend of the family, who had the ******* to say anything among them without offence, coming to visit Philip, after the first compliments and embraces were over, Philip asked him whether the Grecians were at amity with one another. "It ill becomes you," replied Demaratus, "to be so solicitous about Greece, when you have involved your own house in so many dissensions and calamities." He was so convinced by this seasonable reproach, that he immediately sent for his son home, and by Demaratus's mediation prevailed with him to return. But this reconciliation lasted not long; for when Pixodorus, viceroy of Caria, sent Aristocritus to treat for a match between his eldest daughter and Philip's son, Arrhidaeus, hoping by this alliance to secure his assistance upon occasion, Alexander's mother, and some who pretended to be his friends, presently filled his head with tales and calumnies, as if Philip, by a splendid marriage and important alliance, were preparing the way for settling the kingdom upon Arrhidaeus. In alarm at this, he despatched Thessalus, the tragic actor, into Caria, to dispose Pixodorus to slight Arrhidaeus, both illegitimate and a fool, and rather to accept of himself for his son-in-law. This proposition was much more agreeable to Pixodorus than the former. But Philip, as soon as he was made acquainted with this transaction, went to his son's apartment, taking with him Philotas, the son of Parmenio, one of Alexander's intimate friends and companions, and there reproved him severely, and reproached him bitterly, that he should be so degenerate, and unworthy of the power he was to leave him, as to desire the alliance of a mean Carian, who was at best but the slave of a barbarous prince. Nor did this satisfy his resentment, for he wrote to the Corinthians to send Thessalus to him in chains, and banished Harpalus, Nearchus, Erigyius, and Ptolemy, his son's friends and favourites, whom Alexander afterwards recalled and raised to great honour and preferment.
Not long after this, Pausanias, having had an outrage done to him at the instance of Attalus and Cleopatra, when he found he could get no reparation for his disgrace at Philip's hands, watched his opportunity and murdered him. The guilt of which fact was laid for the most part upon Olympias, who was said to have encouraged and exasperated the enraged youth to revenge; and some sort of suspicion attached even to Alexander himself, who, it was said, when Pausanias came and complained to him of the injury he had received, repeated the verse out of Euripides's Medea-"On husband, and on father, and on bride."However, he took care to find out and punish the accomplices of the conspiracy severely, and was very angry with Olympias for treating Cleopatra inhumanly in his absence.
Alexander was but twenty years old when his father was murdered, and succeeded to a kingdom, beset on all sides with great dangers and rancorous enemies. For not only the barbarous nations that bordered on Macedonia were impatient of being governed by any but their own native princes, but Philip likewise, though he had been victorious over the Grecians, yet, as the time had not been sufficient for him to complete his conquest and accustom them to his sway, had simply left all things in a general disorder and confusion. It seemed to the Macedonians a very critical time; and some would have persuaded Alexander to give up all thought of retaining the Grecians in subjection by force of arms, and rather to apply himself to win back by gentle means the allegiance of the tribes who were designing revolt, and try the effect of indulgence in arresting the first motions towards revolution. But he rejected this counsel as weak and timorous, and looked upon it to be more prudence to secure himself by resolution and magnanimity, than, by seeming to truckle to any, to encourage all to trample on him. In pursuit of this opinion, he reduced the barbarians to tranquillity, and put an end to all fear of war from them, he gave rapid expedition into their country as far as the river Danube, where he gave Syrmus, King of the Triballians, an entire overthrow.
And hearing the Thebans were in revolt, and the Athenians in correspondence with them, he immediately marched through the pass of Thermopylae, saying that to Demosthenes, who had called him a child while he was in Illyria and in the country of the Triballians, and a youth when he was in Thessaly, he would appear a man before the walls of Athens.
When he came to Thebes, to show how willing he was to accept of their repentance for what was past, he only demanded of them Phoenix and Prothytes, the authors of the rebellion, and proclaimed a general pardon to those who would come over to him. But when the Thebans merely retorted by demanding Philotas and Antipater to be delivered into their hands, and by a proclamation on their part invited all who would assert the liberty of Greece to come over to them, he presently applied himself to make them feel the last extremities of war. The Thebans indeed defended themselves with a zeal and courage beyond their strength, being much outnumbered by their enemies. But when the Macedonian garrison sallied out upon them from the citadel, they were so hemmed in on all sides that the greater part of them fell in the battle; the city itself being taken by storm, was sacked and razed. Alexander's hope being that so severe an example might terrify the rest of Greece into obedience, and also in order to gratify the hostility of his confederates, the Phocians and Plataeans. So that, except the priests, and some few who had heretofore been the friends and connections of the Macedonians, the family of the poet Pindar, and those who were known to have opposed the public vote for the war, all the rest, to the number of thirty thousand, were publicly sold for slaves; and it is computed that upwards of six thousand were put to the sword.