He made the longest address that day to the Thessalians and other Greeks, who answered him with loud shouts, desiring him to lead them on against the barbarians, upon which he shifted his javelin into his left hand, and with his right lifted up towards heaven, besought the gods, as Callisthenes tells us, that if he was of a truth the son of Jupiter, they would be pleased to assist and strengthen the Grecians. At the same time the augur Aristander, who had a white mantle about him, and a crown of gold on his head, rode by and showed them an eagle that soared just over Alexander, and directed his flight towards the enemy; which so animated the beholders, that after mutual encouragements and exhortations, the horse charged at full speed, and were followed in a mass by the whole phalanx of the foot. But before they could well come to blows with the first ranks, the barbarians shrunk back, and were hotly pursued by Alexander, who drove those that fled before him into the middle of the battle, where Darius himself was in person, whom he saw from a distance over the foremost ranks, conspicuous in the midst of his life-guard, a tall and fine-looking man, drawn in a lofty chariot, defended by an abundance of the best horse, who stood close in order about it ready to receive the enemy. But Alexander's approach was so terrible, forcing those who gave back upon those who yet maintained their ground, that he beat down and dispersed them almost all. Only a few of the bravest and valiantest opposed the pursuit, who were slain in their king's presence, falling in heaps upon one another, and in the very pangs of death striving to catch hold of the horses. Darius now seeing all was lost, that those who were placed in front to defend him were broken and beat back upon him, that he could not turn or disengage his chariot without great difficulty, the wheels being clogged and entangled among the dead bodies, which lay in such heaps as not only stopped, but almost covered the horses, and made them rear and grow so unruly that the frightened charioteer could govern them no longer, in this extremity was glad to quit his chariot and his arms, and mounting, it is said, upon a mare that had been taken from her foal, betook himself to flight. But he had not escaped so either, if Parmenio had not sent fresh messengers to Alexander, to desire him to return and assist him against a considerable body of the enemy which yet stood together, and would not give ground. For, indeed, Parmenio is on all hands accused of having been sluggish and unserviceable in this battle, whether age had impaired his courage, or that, as Callisthenes says, he secretly disliked and envied Alexander's growing greatness. Alexander, though he was not a little vexed to be so recalled and hindered from pursuing his victory, yet concealed the true reason from his men, and causing a retreat to be sounded, as if it were too late to continue the execution any longer, marched back towards the place of danger, and by the way met the news of the enemy's total overthrow and flight.
This battle being thus over, seemed to put a period to the Persian empire; and Alexander, who was now proclaimed King of Asia, returned thanks to the gods in magnificent sacrifices, and rewarded his friends and followers with great sums of money, and places, and governments of provinces. Eager to gain honour with the Grecians, he wrote to them that he would have all tyrannies abolished, that they might live free according to their own laws, and specially to the Plataeans, that their city should be rebuilt, because their ancestors had permitted their countrymen of old to make their territory the seat of the war when they fought with the barbarians for their common liberty. He sent also part of the spoils into Italy, to the Crotoniats, to honour the zeal and courage of their citizen Phayllus, the wrestler, who, in the Median war, when the other Grecian colonies in Italy disowned Greece, that he might have a share in the danger, joined the fleet at Salamis, with a vessel set forth at his own charge. So affectionate was Alexander to all kind of virtue, and so desirous to preserve the memory of laudable actions.