Forewarned by a deserter, Alexander avoided the places where iron spikes had been planted to damage the Macedonian cavalry.[382] He himself, at the head of the Royal Squadron, on the extreme right, led the march obliquely in that direction, keeping his right somewhat in advance. As he neared the enemy, he saw Darius himself with the Persian left centre immediately opposed to him—Persian guards, Indians, Albanians, and Karians. Alexander went on inclining to the right, and Darius stretching his front towards the left to counteract this movement, but still greatly outflanking the Macedonians to the left. Alexander had now got so far to his right, that he was almost beyond the ground levelled by Darius for the operations of his chariots in front. To check any farther movement in this direction, the Baktrian 1000 horse and the Scythians in front of the Persian left, were ordered to make a circuit and attack the Macedonian right flank. Alexander detached against them his regiment of cavalry under Menidas, and the action thus began.[383]
The Baktrian horse, perceiving the advance of Menidas, turned from their circuitous movement to attack him, and at first drove him back until he was supported by the other advanced detachments—Pæonians and Grecian cavalry. The Baktrians, defeated in their turn, were supported by the satrap Bessus with the main body of Baktrians and Scythians in the left portion of Darius’s line. The action was here for some time warmly contested, with some loss to the Greeks; who at length however, by a more compact order against enemies whose fighting was broken and desultory, succeeded in pushing them out of their place in the line, and thus making a partial opening in it.[384]
While this conflict was still going on, Darius had ordered his scythed chariots to charge, and his main line to follow them, calculating on the disorder which he expected that they would occasion. But the chariots were found of little service. The horses were terrified, checked, or wounded, by the Macedonian archers and darters in front; who even found means to seize the reins, pull down the drivers, and kill the horses. Of the hundred chariots in Darius’s front, intended to beat down the Macedonian ranks by simultaneous pressure along their whole line, many were altogether stopped or disabled; some turned right round, the horses refusing to face the protended pikes, or being scared with the noise of pike and shield struck together; some which reached the Macedonian line, were let through without mischief by the soldiers opening their ranks; a few only inflicted wounds or damage.[385]
As soon as the chariots were thus disposed of, and the Persian main force laid open as advancing behind them, Alexander gave orders to the troops of his main line, who had hitherto been perfectly silent,[386] to raise the war-shout and charge at a quick pace; at the same time directing Aretes with the Pæonians to repel the assailants on his right flank. He himself, discontinuing his slanting movement to the right, turned towards the Persian line, and dashed, at the head of all the Companion-cavalry, into that partial opening in it, which had been made by the flank movement of the Baktrians. Having by this opening got partly within the line, he pushed straight towards the person of Darius; his cavalry engaging in the closest hand-combat, and thrusting with their short pikes at the faces of the Persians. Here, as at the Granikus, the latter were discomposed by this mode of fighting—accustomed as they were to rely on the use of missiles, with rapid wheeling of the horse for renewed attack.[387] They were unable to prevent Alexander and his cavalry from gaining ground and approaching nearer to Darius; while at the same time, the Macedonian phalanx in front, with its compact order and long protended pikes, pressed upon the Persian line opposed to it. For a short interval, the combat here was close and obstinate; and it might have been much prolonged—since the best troops of Darius’s army—Greeks, Karians, Persian guards, regal kinsmen, etc., were here posted,—had the king’s courage been equal to that of his soldiers. But here, even worse than at Issus, the flight of the army began with Darius himself. It had been the recommendation of Cyrus the younger, in attacking the army of his brother Artaxerxes at Kunaxa, to aim the main blow at the spot where his brother was in person—since he well knew that victory there was victory everywhere. Having already once followed this scheme successfully at Issus, Alexander repeated it with still more signal success at Arbêla. Darius, who had long been in fear, from the time when he first beheld his formidable enemy on the neighboring hills, became still more alarmed when he saw the scythed chariots prove a failure, and when the Macedonians, suddenly breaking out from absolute silence into an universal war-cry, came to close quarters with his troops, pressing towards and menacing the conspicuous chariot on which he stood.[388] The sight and hearing of this terrific mêlée, combined with the prestige already attaching to Alexander’s name, completely overthrew the courage and self-possession of Darius. He caused his chariot to be turned round, and himself set the example of flight.[389]
From this moment, the battle, though it had lasted so short a time, was irreparably lost. The king’s flight, followed of course immediately by that of the numerous attendants around him, spread dismay among all his troops, leaving them neither centre of command, nor chief to fight for. The best soldiers in his army, being those immediately around him, were under these circumstances the first to give way. The fierce onset of Alexander with the Companion-cavalry, and the unremitting pressure of the phalanx in front was obstructed by little else than a mass of disordered fugitives. During the same time, Aretes with his Pæonians had defeated the Baktrians on the right flank,[390] so that Alexander was free to pursue the routed main body,—which he did most energetically. The cloud of dust raised by the dense multitude is said to have been so thick, that nothing could be clearly seen, nor could the pursuers distinguish the track taken by Darius himself. Amidst this darkness, the cries and noises from all sides were only the more impressive; especially the sound from the whips of the charioteers, pushing their horses to full speed.[391] It was the dust alone which saved Darius himself from being overtaken by the pursuing cavalry.
While Alexander was thus fully successful on his right and centre, the scene on his left under Parmenio was different. Mazæus, who commanded the Persian right, after launching his scythed chariots (which may possibly have done more damage than those launched on the Persian left, though we have no direct information about them), followed it up by vigorously charging the Grecian and Thessalian horse in his front, and also by sending round a detachment of cavalry to attack them on their left flank.[392] Here the battle was obstinately contested, and success for some time doubtful. Even after the flight of Darius, Parmenio found himself so much pressed, that he sent a message to Alexander. Alexander, though full of mortification at relinquishing the pursuit, checked his troops, and brought them back to the assistance of his left, by the shortest course across the field of battle. The two left divisions of the phalanx, under Simmias and Kraterus, had already stopped short in the pursuit, on receiving the like message from Parmenio; leaving the other four divisions to follow the advanced movement of Alexander.[393] Hence there arose a gap in the midst of the phalanx, between the four right divisions, and the two left; into which gap a brigade of Indian and Persian cavalry darted, galloping through the midst of the Macedonian line to get into the rear and attack the baggage.[394] At first this movement was successful, the guard was found unprepared, and the Persian prisoners rose at once to set themselves free; though Sisygambis, whom these prisoners were above measure anxious to liberate, refused to accept their aid, either from mistrust of their force, or gratitude for the good treatment received from Alexander.[395] But while these assailants were engaged in plundering the baggage, they were attacked in the rear by the troops forming the second Macedonian line, who though at first taken by surprise, had now had time to face about and reach the camp. Many of the Persian brigade were thus slain, the rest got off as they could.[396]
Mazæus maintained for a certain time fair equality, on his own side of the battle, even after the flight of Darius. But when, to the paralyzing effect of that fact in itself, there was added the spectacle of its disastrous effects on the left half of the Persian army, neither he nor his soldiers could persevere with unabated vigor in a useless combat. The Thessalian and Grecian horse, on the other hand, animated by the turn of fortune in their favor, pressed their enemies with redoubled energy and at length drove them to flight; so that Parmenio was victor, on his own side and with his own forces, before the succors from Alexander reached him.[397]
In conducting those succors, on his way back from the pursuit, Alexander traversed the whole field of battle, and thus met face to face some of the best Persian and Parthian cavalry, who were among the last to retire. The battle was already lost, and they were seeking only to escape. As they could not turn back, and had no chance for their lives except by forcing their way through his Companion-cavalry, the combat here was desperate and murderous; all at close quarters, cut and thrust with hand weapons on both sides contrary to the Persian custom. Sixty of the Macedonian cavalry were slain; and a still greater number, including Hephæstion, Kœnus, and Menidas, were wounded, and Alexander himself encountered great personal danger. He is said to have been victorious; yet probably most of these brave men forced their way through and escaped, though leaving many of their number on the field.[398]
Having rejoined his left, and ascertained that it was not only out of danger, but victorious, Alexander resumed his pursuit of the flying Persians, in which Parmenio now took part.[399] The host of Darius was only a multitude of disorderly fugitives, horse and foot mingled together. The greater part of them had taken no share in the battle. Here, as at Issus, they remained crowded in stationary and unprofitable masses, ready to catch the contagion of terror and to swell the number of runaways, so soon as the comparatively small proportion of real combatants in the front had been beaten. On recommencing the pursuit, Alexander pushed forward with such celerity, that numbers of the fugitives were slain or taken, especially at the passage of the river Lykus;[400] where he was obliged to halt for a while, since his men as well as their horses were exhausted. At midnight, he again pushed forward, with such cavalry as could follow him, to Arbêla, in hopes of capturing the person of Darius. In this he was disappointed, though he reached Arbêla the next day. Darius had merely passed through it, leaving an undefended town, with his bow, shield, chariot, a large treasure, and rich equipage, as prey to the victor. Parmenio had also occupied without resistance the Persian camp near the field of battle, capturing the baggage, the camels, and the elephants.[401]
To state anything like positive numbers of slain or prisoners, is impossible. According to Arrian, 300,000 Persians were slain, and many more taken prisoners. Diodorus puts the slain at 90,000, Curtius at 40,000. The Macedonian killed were, according to Arrian, not more than 100—according to Curtius, 300: Diodorus states the slain at 500, besides a great number of wounded.[402] The estimate of Arrian is obviously too great on one side, and too small on the other; but whatever may be the numerical truth, it is certain that the prodigious army of Darius was all either killed, taken, or dispersed, at the battle of Arbêla. No attempt to form a subsequent army ever succeeded; we read of nothing stronger than divisions or detachments. The miscellaneous contingents of this once mighty empire, such at least among them as survived, dispersed to their respective homes and could never be again mustered in mass.