The Two Armies

In studying the campaigns of Alexander, we possess the peculiar advantage of deriving our information from two of Alexander’s generals, who bore an important part in all his enterprises: Aristobulus and Ptolemy.

Continuing Alexander the Great Wins Battle of Gaugamela,
our selection from Fifteen Decisive Battles of the World by Sir Edward S. Creasy published in 1851. The selection is presented in nine easy 5-minute installments. For works benefiting from the latest research see the “More information” section at the bottom of these pages.

Previously in Alexander the Great Wins Battle of Gaugamela.

Time: 331 BC
Place: East of Mosul, Iraq

The hardy mountaineers of Afghanistan, Bokhara, Khiva, and Tibet were then, as at present, far different from the generality of Asiatics in warlike spirit and endurance. From these districts Darius collected large bodies of admirable infantry; and the countries of the modern Kurds and Turkomans supplied, as they do now, squadrons of horsemen, hardy, skillful, bold, and trained to a life of constant activity and warfare. It is not uninteresting to notice that the ancestors of our own late enemies, the Sikhs, served as allies of Darius against the Macedonians. They are spoken of in Arrian as Indians who dwelt near Bactria. They were attached to the troops of that satrapy, and their cavalry was one of the most formidable forces in the whole Persian army.

Besides these picked troops, contingents also came in from the numerous other provinces that yet obeyed the Great King. Altogether, the horse are said to have been forty thousand, the scythe-bearing chariots two hundred, and the armed elephants fifteen in number. The amount of the infantry is uncertain; but the knowledge which both ancient and modern times supply of the usual character of oriental armies, and of their populations of camp-followers, may warrant us in believing that many myriads were prepared to fight or to encumber those who fought for the last Darius.

The position of the Persian King near Mesopotamia was chosen with great military skill. It was certain that Alexander, on his return from Egypt, must march northward along the Syrian coast before he attacked the central provinces of the Persian empire. A direct eastward march from the lower part of Palestine across the great Syrian Desert was then, as ever, utterly impracticable. Marching eastward from Syria, Alexander would, on crossing the Euphrates, arrive at the vast Mesopotamian plains. The wealthy capitals of the empire, Babylon, Susa, and Persepolis would then lie to the south; if he marched down through Mesopotamia to attack them, Darius might reasonably hope to follow the Macedonians with his immense force of cavalry, and, without even risking a pitched battle, to harass and finally overwhelm them.

We may remember that three centuries afterward a Roman army under Crassus was thus actually destroyed by the oriental archers and horsemen in these very plains, and that the ancestors of the Parthians who thus vanquished the Roman legions served by thousands under King Darius. If, on the contrary, Alexander should defer his march against Babylon, and first seek an encounter with the Persian army, the country on each side of the Tigris in this latitude was highly advantageous for such an army as Darius commanded, and he had close in his rear the mountainous districts of Northern Media, where he himself had in early life been satrap, where he had acquired reputation as a soldier and a general, and where he justly expected to find loyalty to his person, and a safe refuge in case of defeat.

[Mitford’s remarks on the strategy of Darius in his last campaign are very just. After having been unduly admired as a historian, Mitford is now unduly neglected. His partiality and his deficiency in scholarship have been exposed sufficiently to make him no longer a dangerous guide as to Greek politics, while the clearness and brilliance of his narrative, and the strong common sense of his remarks (where his party prejudices do not interfere), must always make his volumes valuable as well as entertaining.]

His great antagonist came on across the Euphrates against him, at the head of an army which Arrian, copying from the journals of Macedonian officers, states to have consisted of forty thousand foot and seven thousand horse. In studying the campaigns of Alexander, we possess the peculiar advantage of deriving our information from two of Alexander’s generals of division, who bore an important part in all his enterprises. Aristobulus and Ptolemy — who afterward became king of Egypt — kept regular journals of the military events which they witnessed, and these journals were in the possession of Arrian when he drew up his history of Alexander’s expedition.

The high character of Arrian for integrity makes us confident that he used them fairly, and his comments on the occasional discrepancies between the two Macedonian narratives prove that he used them sensibly. He frequently quotes the very words of his authorities; and his history thus acquires a charm such as very few ancient or modern military narratives possess. The anecdotes and expressions which he records we fairly believe to be genuine, and not to be the coinage of a rhetorician, like those in Curtius. In fact, in reading Arrian, we read General Aristobulus and General Ptolemy on the campaigns of the Macedonians, and it is like reading General Jomini or General Foy on the campaigns of the French.

The estimate which we find in Arrian of the strength of Alexander’s army seems reasonable enough, when we take into account both the losses which he had sustained and the reinforcements which he had received since he left Europe. Indeed, to Englishmen, who know with what mere handfuls of men our own generals have, at Plassy, at Assaye, at Meeanee, and other Indian battles, routed large hosts of Asiatics, the disparity of numbers that we read of in the victories won by the Macedonians over the Persians presents nothing incredible. The army which Alexander now led was wholly composed of veteran troops in the highest possible state of equipment and discipline, enthusiastically devoted to their leader, and full of confidence in his military genius and his victorious destiny.

The celebrated Macedonian phalanx formed the main strength of his infantry. This force had been raised and organized by his father, Philip, who, on his accession to the Macedonian throne, needed a numerous and quickly formed army, and who, by lengthening the spear of the ordinary Greek phalanx, and increasing the depth of the files, brought the tactics of armed masses to the highest extent of which it was capable with such materials as he possessed. He formed his men sixteen deep, and placed in their grasp the sarissa, as the Macedonian pike was called, which was four-and-twenty feet in length, and, when couched for action, reached eighteen feet in front of the soldier; so that, as a space of about two feet was allowed between the ranks, the spears of the five files behind him projected in front of each front-rank man.

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