Lastly, to turn to the Macedonian army, we cannot but recognise in its organisation a rare combination of fortunate circumstance and great military talent. The moral superiority of the Greek army, as opposed to the material superiority of the Persians, had been more and more gloriously proven in almost every war for the last two centuries. The more highly the art of war was developed among the Greeks by civil and foreign strife, the more formidable did they become to the troops of the Persian empire; Alexander’s army, full of martial ardour and proud memories, skilled in all the technicalities of the military profession, and notable by reason of its thoroughly practical organisation as the first strategic body known to history, bore in itself the certainty of victory.
The armies of Asia have always been characterised by the vehemence of their onslaught, their overwhelming numbers, and their wild rushes hither and thither, which make them formidable even in flight. In addition to this there were many thousands of Greeks in Persian pay, so that Alexander could not reckon on having to wage war merely on barbarians, but had to look for Hellenic arms, courage, and military skill, on the part of the enemy. Finally, in accordance with the natural scope of his great enterprise, the mobility necessary for taking offensive, and the stability essential to military occupation, had both to be considered in the constitution of his army.
THE SIZE OF THE ARMY
In Philip’s time the Macedonian forces had consisted of thirty thousand infantry and from three to four thousand horsemen. Alexander had led about the same number of troops against Thebes. On his departure for Asia he left twelve thousand foot-soldiers and fifteen hundred mounted men in Macedonia under the command of Antipater, and their place was taken by eighteen hundred Thessalian knights, five thousand Greek mercenaries, and seven thousand heavy-armed troops furnished by the Greek states. Besides these he had in his following five thousand Triballians, Odrysians, Illyrians, etc., from one to two thousand archers and Agrianian light infantry, Greek cavalry to the number of six hundred, Thracian and Pæonian to the number of nine hundred. The sum total of his troops therefore amounted to not much over 30,000 infantry and a little more than 5,000 horse. This, with slight divergencies suggested by the details of the narrative, is the estimate of Diodorus. Ptolemy Lagi gives the same figures in his Memorabilia, and Arrian repeats them after him. When Anaximenes reckons thirty-four thousand men on foot and five thousand five hundred on horseback he perhaps includes the corps which had already been despatched to Asia by Philip. The estimate of Callisthenes, 40,000 infantry, is obviously too high.
The whole body of infantry and cavalry was not divided into legions or brigades, but into troops bearing the same weapons and, to some extent, recruited from the same district. The very advantages of a Macedonian army rendered necessary an arrangement which would be unsatisfactory under present conditions; the phalanx would have been no phalanx if it had fought with cavalry, light infantry, and Thracian slingers all combined into a complete army in miniature. It is the general use of small fighting units which has made it necessary for the parts of an army to be self sufficient, and to repeat on a small scale the organisation of the whole. Against such an enemy as the Asiatic hordes—collected together for a pitched battle without previous discipline or training, giving up all for lost after a single defeat, and gaining nothing but renewed danger by a victory over organised troops—against such an enemy, solid and homogeneous masses have the advantage of simplicity, weight, and internal stability, and in the same region where Alexander’s phalanx overpowered the army of Darius the Roman legions succumbed to the vehement onslaught of the Parthians. On the whole, Alexander’s army was well adapted for such pitched battles, and hence the bulk of it consisted of his phalanxes and heavy cavalry.
THE PHALANX AND THE CAVALRY
A Soldier of Alexander’s Phalanx
The peculiar character of the phalanx was due to the weapons and co-ordination of the individual members. They were heavily armed according to Greek ideas, equipped with helmets, armour, and a shield which protected the whole body, and their chief weapons were the Macedonian sarissa, a lance more than twenty feet long, and the short Greek sword. Intended solely for close fighting in the mass, they had to be so arranged as to be able, on the one hand, calmly to await the fiercest onset of the enemy, and on the other, to be sure of breaking through the opposing ranks with a rush. They therefore usually stood sixteen deep, the lances of the first five files projecting beyond the front, an impenetrable and indeed unassailable barrier to the advancing enemy; the hinder files laid their sarissa on the shoulders of those in front, so that the charge of the phalanx was irresistible from the double force of weight and motion. Nothing but the thorough gymnastic training of the individual members of the phalanx rendered possible the unity, precision, and rapidity necessary for the very difficult evolutions of a body of men crowded into so small a space. Alexander had about eighteen thousand of these heavy-armed soldiers, the so-called foot-guards, and at the beginning of the campaign they were divided into six divisions under the generals Perdiccas, Cœnus, Craterus, Amyntas the son of Andromenes, Meleager, and Philip the son of Amyntas. The nucleus of these troops at least was Macedonian, and the divisions were named after the Macedonian districts from which they were recruited; thus the division under Cœnus came from Elimea, that under Perdiccas from Orestis and Lyncestis, that of Philip (afterwards led by Polysperchon) from Stymphæa, etc.
What the phalanx was among the infantry, the Macedonian and Thessalian ilai were among the cavalry. Both were composed of heavy-armed soldiers and consisted of the nobility of Macedonia and Thessaly; equal in arms, in birth, and in fame, they vied with each other in distinguishing themselves in the eyes of the king, who usually fought at their head. The importance of this arm to Alexander’s enterprise was proved in almost every fight; terrible alike in single combat and in charges in the mass, their discipline and armour rendered them superior to the light Asiatic cavalry, however great their numbers, and their onslaught on the enemy’s foot was generally decisive. According to the estimate of Diodorus, the knighthood of Macedonia and Thessaly each consisted of five hundred knights; but he, like Callisthenes, sets the cavalry of the Macedonian army at no more than four thousand five hundred men, while the best authorities place it at over five thousand. The two bodies of knights were armed alike—Calas, the son of Harpalus, had command of the Thessalians; Philotas, the son of Parmenion, of the Macedonians.