The first consisted of light-armed troops, horse and foot, of good quality, which were especially intended to act against the enemy’s chariots. The next was the main line of battle, and contained the phalanx with the rest of the heavy infantry in the centre, the heavy cavalry upon the two wings. The third line consisted of light troops, chiefly horse, and was instructed to act against such of the Persians as should outflank the Macedonian main line and so threaten their rear. As at Issus, Alexander took the command of the right wing himself, and assigned the left to Parmenio.
As the two armies drew near, Alexander, who found himself greatly outflanked on both wings, and saw in front of him smooth ground carefully prepared for the operations of chariots and cavalry, began a diagonal movement towards the right, which tended at once to place him beyond the levelled ground, and to bring him in contact with his enemy’s left wing rather than with his direct front. The movement greatly disconcerted his adversary, who sought to prevent it by extending and advancing his own left, which was soon engaged with Alexander’s right in a fierce hand-to-hand conflict. Alexander still pressed his slanting movement, and in resisting it Darius’s left became separated from his centre, while at the same time he was forced to give the signal for launching the chariots against the foe sooner than he had intended, and under circumstances that were not favorable. The effect of the operation was much the same as at Cunaxa. Received by the Macedonian light-armed, the chariots were mostly disabled before the enemy’s main line was reached; the drivers were dragged from the chariot-boards; and the horses were cut to pieces. Such as escaped this fate and charged the Macedonian line, were allowed to pass through the ranks, which opened to receive them, and were then dealt with by grooms and others in the rear of the army.
No sooner had the chariot attack failed, and the space between the two lines of battle become clear, than Alexander, with the quick eye of a true general, saw his opportunity: to resist his flank movement, the Bactrians and Sacae with the greater part of the left wing had broken off from the main Persian line, and in pressing towards the left had made a gap between their ranks and the centre. Into this gap the Macedonian king, at the head of the “Companion” cavalry and a portion of the phalanx, plunged. Here he found himself in the near neighborhood of Darius, whereupon he redoubled the vigor of his assault, knowing the great importance of any success gained in this quarter. The Companions rushed on with loud cries, pressing with all their weight, and thrusting their spears into the faces of their antagonists—the phalanx, bristling with its thick array of lances, bore them down. Alexander found himself sufficiently near Darius to hurl a spear at him, which transfixed his charioteer. The cry arose that the king had fallen, and the ranks at once grew unsteady. The more timid instantly began to break and fly; the contagion of fear spread; and Darius was in a little while almost denuded of protection on one side. Seeing this, and regarding the battle as lost, since his line was broken, his centre and left wing defeated, while only his right wing remained firm, the Persian monarch yielded to his alarm, and hastily quitting the field, made his way to Arbela. The centre and left fled with him. The right, which was under the command of the Syrian satrap, Mazseus, made a firmer stand. On this side the chariots had done some damage, and the horse was more than a match for the Thessalian cavalry. Parmenio found himself in difficulties about the time when the Persian king fled. His messengers detained a part of the phalanx, which was about to engage in the pursuit, and even recalled Alexander, who was hastening upon the track of Darius. The careful prince turned back, but before he could make his way through the crowd of fugitives to the side of his lieutenant, victory had declared in favor of the Macedonians in this part of the field also. Mazseus and his troops, learning that the king was fled, regarded further resistance as useless, and quitted the field. The Persian army hurriedly recrossed the Zab, pursued by the remorseless conquerors, who slew the unresisting fugitives till they were weary of slaughter. Arrian says that 300,000 fell, while a still larger number were taken prisoners. Other writers make the loss considerably less. All, however, agree that the army was completely routed and dispersed, that it made no attempt to rally, and gave no further trouble to the conqueror.
The conduct of Darius in this—the crisis of his fate—cannot be approved; but it admits of palliation, and does not compel us to withdraw from him that respectful compassion which we commonly accord to great misfortunes. After Issus, it was his duty to make at least one more effort against the invader. To this object he addressed himself with earnestness and diligence. The number and quality of the troops collected at Arbela attests at once the zeal and success of his endeavors. His choice and careful preparation of the field of battle are commendable; in his disposition of his forces there is nothing with which to find fault. Every arm of the service had full room to act; all were brought into play; if Alexander conquered, it was because he was a consummate general, while at the same time he commanded the best troops in the world. Arbela was not, like Issus, won by mere fighting. It was the leader’s victory, rather than the soldiers. Alexander’s diagonal advance, the confusion which it caused, the break in the Persian line, and its prompt occupation by some of the best cavalry and a portion of the phalanx, are the turning-points of the engagement. All the rest followed as a matter of course. Far too much importance has been assigned to Darius’s flight, which was the effect rather than the cause of victory. When the centre of an Asiatic army is so deeply penetrated that the person of the monarch is exposed and his near attendants begin to fall, the battle is won. Darius did not—indeed he could not—“set the example of flight.” Hemmed in by vast masses of troops, it was not until their falling away from him on his left flank at once exposed him to the enemy and gave him room to escape, that he could extricate himself from the melee.
No doubt it would have been nobler, finer, more heroic, had the Persian monarch, seeing that all was lost, and that the Empire of the Persians was over, resolved not to outlive the independence of his country. Had he died in the thick of the fight, a halo of glory would have surrounded him. But, because he lacked, in common with many other great kings and commanders, the quality of heroism, we are not justified in affixing to his memory the stigma of personal cowardice. Like Pompey, like Napoleon, he yielded in the crisis of his fate to the instinct of self-preservation. He fled from the field where he had lost his crown, not to organize a new army, not to renew the contest, but to prolong for a few weeks a life which had ceased to have any public value.
It is needless to pursue further the dissolution of the Empire. The fatal blow was struck at Arbela—all the rest was but the long death-agony. At Arbela the crown of Cyrua passed to the Macedonian; the Fifth Monarchy came to an end. The HE-GOAT, with the notable horn between his eyes, had come from the west to the ram which had two horns, and had run into him with the fury of his power. He had come close to him, and, moved with choler, had smitten the ram and broken his two horns—there was no power in the ram to stand before him, but he had cast him down to the ground and stamped upon him—and there was none to deliver the ram out of his hand.