south whose infantries were based on long-established traditions of middle-class heavy infantry, the so-called hoplites who dominated the Classical Age. These soldiers wore bronze breastplates and greaves, carried a circular, three-foot in diameter, shield, and a roughly seven-foot long thrusting spear. They fought typically in a compact unit, the phalanx. Cavalry and light-armed troops played a secondary role, protecting the flanks and rear of these formations, and often pursuing the defeated after the battle was won. Macedonia, then, at the start of Philip’s reign, was disunited with much of the interior dominated by a powerful, land-holding aristocracy and the coast by independent Greek cities, and, at the time of his accession, suffering foreign occupation.
To drive out the Illyrians, Philip created the famous Macedonian phalanx, which would dominate Western warfare for almost two centuries. Faced with a population that could not afford the hoplite panoply and insufficient royal revenues, Philip was forced to change the very nature of the infantry panoply and tactics. He also had to deal with a Macedonian army that had been virtually annihilated in the recent battle. Whereas the hoplites were previously the offensive key to victory, Philip made his new infantry primarily a defensive force. In his new army, the infantryman was equipped with a 15-foot pike (the sarissa),3 a 2-foot diameter shield hung from the neck and shoulder, and little else in the way of defensive armor. This new panoply was cheaper and the soldier required far less training. Over time, the pikes lengthened so that in the later Hellenistic period they might be as long as 24 feet (Polyb. 18.29.2). Such formations of tightly packed pikes could easily defend against frontal assaults by either hoplites or cavalry. These troops resembled the later Swiss pikemen of the early modern era, a similarity noted by Nicolo Machiavelli.4 The inspiration for this innovation by the new Macedonian king is unclear. Modern historians cite earlier experiments with longer spears by other commanders, or their occasional use by neighboring tribal peoples, but it is also possible that Philip simply adopted and adapted the long spears traditionally used in hunting.5 Whatever the inspiration, it was Philip who realized the potential and brought it to fruition.
While others may have seen the potential, they lacked the means to make a pike phalanx effective.6 To a great extent invulnerable to frontal attacks on level ground, a pike phalanx was incredibly vulnerable on the flanks and rear, and found it difficult to maintain its impenetrable front on broken ground (Polyb. 18.30.11, 31.5–6). In order to compensate for the weaknesses in this new infantry formation the Macedonian king maintained a force of infantry guards trained both as pike bearers and as hoplites, initially called the Pezhetairoi and later the Hypaspists.7 These troops represented a standing, national, professional force, and typically occupied the right wing. When used as hoplites, they gave more flexibility on the wing, most often engaging the enemy infantry first. Beginning as a royal guard, they likely numbered only a few hundred. Their eventual strength was 3000. More mobile than the “typical” Macedonian phalangite, they were regularly equipped for hand-to-hand warfare. The most significant change for these elite troops was that the hoplite’s heavy metal breastplate had been replaced with one of linen or leather, reinforced with iron plates. As Alexander marched deeper into Asia, more units were equipped in the manner of the Hypaspists. This was especially the case after the dismissal of the allied Greek heavy infantry of hoplites (Arr. Anab. 3.19.6; cf. Diod. Sic. 17.17.3). It has also been recently argued that as Alexander continued into Asia he required more of these modified hoplite units, and many of his sarissa battalions were converted, and acquired the name of asthetairoi.8
But the key to Philip’s new army was that he possessed a great advantage over those who may have experimented with the pike earlier—the native cavalry of Macedonia. Not only would the cavalry protect the vulnerable phalanx but, in Philip’s new model army, it would become the principal attacking force. With the Macedonian infantry occupying the full attention of the enemy, the cavalry, in what has been described as the “hammer and anvil” tactic, would probe for weaknesses that could then be exploited for victory. The infantry became the anvil on which the hammer of the cavalry would smash the enemy. With this new army, Philip subdued his enemies and his son Alexander conquered the Persian Empire. Macedonian cavalry was so expert that, in a wedge formation, it could punch through a weakened or gapped infantry line.9
This use of what is currently referred to as “Combined Arms” was augmented further by Philip and especially by his son Alexander with the incorporation of light-armed infantry and cavalry. In addition to the heavy infantry units, Philip’s new model army included archers, slingers, and significant numbers of light-armed infantry, the peltasts.10 Light infantry typically wore little armor except a helmet and fought as javelin men, slingers, or archers. Their formations were open as opposed to the dense, compact nature of the phalanx. The elite light infantry were the Agrianes, javelin men from a dependent ally centered in what is today Bulgaria. These were likely incorporated into Philip’s army and were used extensively by Alexander. They are often included in that commander’s flying columns where speed was paramount. Typically, battles began with attacks of slingers, archers, and javelin men, whose attacks from range were designed to disrupt the cohesiveness of the enemy infantry line. But they were also often used to shield the flanks and defend against enemy cavalry, and, in Asia in particular, against chariots and/or elephants. Alexander’s army that crossed to Asia included 7,000 additional light-armed troops. To these, as he penetrated deeper into Asia, were added additional light-armed auxiliaries from those areas brought under his domination. In 329, Alexander included a unit of 1,000 Iranian horse archers (hippotoxotai) in his grand army. These were used to great effect at the Battle on the Hydaspes against the chariots of the Indian prince Porus. Additionally, in this battle, Bactrian, Sogdianian, and Scythian cavalry were employed by Alexander (Arr. Anab. 5.12.2–3). Earlier, Persian scythed chariots at Gaugamela also proved ineffective. These chariots, outfitted with blades that extended from the wheel axle three feet on each side (Liv. 37.41.7–9), were met by Alexander’s Agrianians and other javelin men who disabled most of their drivers with their javelins. Those chariots that did make it through the barrage of javelins charged the Macedonian phalanx, which simply opened up avenues in their ranks through which the chariots passed harmlessly (Arr. Anab. 3.13.5–6).11 Later, in Babylon, Alexander incorporated both Iranian cavalry in traditional equipment and Persian infantry units. In 323, the Macedonian king received 20,000 Persian infantry and additionally units of Cossaeans and Tapurians (Arr. Anab. 7.23.1).
Chaeronea and Combined Arms
The battle that gave Philip hegemony in Greece, fought near the city of Chaeronea in 338, demonstrates the effectiveness of his new model army.12 Here his army numbered roughly 30,000 mostly Macedonian heavy infantrymen, 2,000 heavy Macedonian cavalry, known as the Companions, and an unknown number of light infantry and cavalry. Heavy cavalry typically wore breastplates, shoulder guards, and helmets; they also carried lances, often shortened versions of the infantry sarissa, and secondarily swords. Light cavalry were usually unarmored and equipped with bows or javelins. Philip faced a similarly sized combined Greek force consisting primarily of Athenian and Theban hoplites. The Athenians took up a position on the left wing opposite Philip and the Hypaspists, the Thebans the right, with other allies in the center. The Greek army was arranged in a defensive position, its left flank anchored by the rising foothills of Mount Thurium, the right resting against the Cephisus River. The foothills and the river bed were to be covered by light-armed infantry and light cavalry by both sides. The Greek line, about two miles in length, was consequently relatively secure on both flanks, leaving little room for the unopposed operation of enemy cavalry or light-armed troops, and thus seemingly negating Philip’s distinct advantage in cavalry. Facing this strong Greek defensive position, the Macedonian king decided on a complicated series of maneuvers to take advantage especially of the inexperienced Athenians. At first, he advanced his forces in echelon, with his right, as usual, under his personal command and containing the elite Hypaspists, here armed as hoplites13 and perhaps already 3,000 strong, to engage the Athenians before committing the Macedonian left against the more experienced Thebans. Given the nature of the battlefield and the size of the respective armies, the battle would be fought at least initially with full frontal infantry assaults.
