A distinction between mercenaries and allied troops certainly existed within the Macedonian order of battle; we saw this with the Thessalian cavalry for example. The distinction drawn by Alexander was not sharp, however, and could lead to some confusion. We must first therefore clarify what these terms actually mean before we consider the individual contingents themselves.
The meaning of the term ‘mercenary’ would seem at first sight obvious: a soldier who fights for pay. But of course everyone in Alexander’s army was being paid, including the Macedonian and allied contingents. I believe that we can narrow the meaning down to ‘someone who fights without a political imperative’, that is a soldier who is not compelled to fight by his city-state, but does so purely for personal reasons. The distinction therefore becomes a little clearer, but the status of the Balkan troops in the army is still problematic. They are one of the contingents whose status changed whilst on campaign; the Balkan troops came from peoples who were more or less formally subject to the king of Macedonia, so that it is difficult to make the distinction between whether they were mercenaries or allies. It is perhaps best to avoid a splitting of hairs and to call them all mercenaries, because if they were allies in the first place they certainly became mercenaries later. I will here consider them amongst the allied contingent, as they were initially of that status, and Diodorus certainly does not include them amongst the mercenaries in his troop list of 334 BC.
By the time of the accession of Alexander in Macedonia, mercenary soldiers formed an integral part, not just of the Macedonian army, but also that of Persia and a number of the Greek city-states. The mercenary soldier himself, however, had undergone considerable change. In the fifth century, mercenaries were few in number and employment opportunities were limited. Their first large scale employment in Greece was during the Peloponnesian War, and was at first confined to the Spartan side, Athens having no access to the large recruiting grounds of Arcadia. It is also the case that Pericles’ defensive strategy had little need of mercenaries. Athens’ first recorded use of hoplite mercenaries was on the Sicilian expedition, and even here there were only 250 ‘Mantineans and other mercenary troops’. Persia tended not to employ Greek mercenaries in large numbers in the fifth century, the first large scale employment being Cyrus’
force of 10,000 so brilliantly described by Xenophon. Mercenaries in the fifth century tended to be grouped into one of the following classifications:
• Archers, often from Crete – Archery, throughout all periods of history, was a specialized field and required considerable training. It was very difficult for a citizen hoplite to acquire the necessary skills and so specialists were hired. Crete is often mentioned as a source of such troops throughout the fifth and fourth centuries, and it even furnished a contingent in Alexander’s army; although Alexander also employed a native Macedonian contingent of archers.
• Cavalry – Usually few in number, primarily because of the expense involved, and because the geography of Greece also generally did not lend itself well to cavalry engagements, with a few notable topographical exceptions.
• Hoplites – Troops armed and equipped in the same manner as a citizen soldier; a heavily armed infantryman wearing a breastplate and often greaves, and carrying a spear. Their main offensive weapon was weight of numbers, hoplite battles could perhaps be thought of as a giant rugby scrum. Heavily-armed hoplites were the main fighting force on either side in the fifth and into the fourth century.
• Peltasts – Light-armed troops carrying a small shield and little or no body armour. Their effectiveness was based almost entirely on their mobility. Most mercenaries in the fourth century fell into this group after the ‘reforms of Iphicrates’ early in that century.
Iphicrates was born towards the end of the fifth century into a poor and rather obscure Athenian family. Despite his lowly background he rose to a position of command in Athens, fighting in a number of campaigns including the Corinthian War and the Social War, he also spent time in Persian service after the Peace of Antalcidas. Diodorus places his peltast reforms after 374, following his Persian sojourn, using his experiences prior to that date to develop this new type of soldier.93 The exact dating of the reforms is not relevant here, but their nature certainly is, as it was this type of soldier that constituted the bulk of Alexander’s mercenary forces. I have also tried to argue earlier that Alexander’s heavy infantry were essentially a version of Iphicratean peltasts, being equipped as they were with a small shield and very little body armour.
The primary sources of information that we have for the peltast reforms of Iphicrates are Diodorus and Nepos, both of whose accounts are very similar. According to them the most significant changes were as follows:
Iphicrates replaced the large (shield) of the Greeks by the light pelte, which had the advantage that it protected the body while allowing the wearer more freedom of movement; the soldiers who had formerly carried the [large hoplite shield] and who were called hoplites, were henceforth called peltastsafter the name of their new shields; their new spears were half as long again or even twice as long as the old ones, the new swords were also double in length, In addition Iphicrates introduced light and easily untied footwear, and the bronze harness was replaced by a linen covering, which although it was lighter, still protected the body.
Diodorus regards these changes as having been introduced into the existing hoplite troops and in the process discounts the possibility of already existing peltast-style light infantry. Diodorus’ failure to realize the existence of peltast troops before Iphicrates is indeed very striking. In this omission Diodorus shows his serious lack of understanding of the military situation of the day. Modern commentators have frequently been struck with the absurdity of this, and have taken up an opposite attitude. For them the change was a trivial one and consisted chiefly in the standardizing of the existing, but rather haphazard, peltast equipment. This argument, however, simply will not do. It assumes that the light-armed skirmishers of earlier narratives were equipped in the same manner that Diodorus describes. This simply cannot be the case; light-armed skirmishers would not have carried a sword and spear twice the length of those carried by hoplites. Earlier narratives also tell of peltasts actually throwing their spears. If Iphicrates was standardizing that which already existed then why did he not provide his troops with these throwing spears? We are surely not to believe that they carried these as well. Some other explanation must be sought.
Was Iphicrates actually inventing a new type of peltast, one with specific and specialized equipment? The other extreme view is that Iphicratean peltasts were in no way different from Thracian peltasts. On this interpretation, Iphicrates’ reforms were of little significance, as troops of exactly the same type existed already in Thrace. The truth probably lies somewhere between these two extreme positions. There was probably no uniformity of peltast equipment before Iphicrates, some using primarily throwing spears, some longer spears, still others using swords of various sizes. The size of the shield probably varied too. I suspect therefore that Iphicrates studied the light infantry of his day and based his reforms around choosing from the various groups the equipment that best suited the type of soldier that he was trying to create. We may see Iphicrates therefore not as creating something entirely new, or as standardizing that which already existed, but as refining the equipment and tactics of the peltasts of his day.
Mercenaries had not been a significant part of the military forces of the city-states in the fifth century. There was, on the one hand, very little fiscal means to support such troops, and, on the other, a generally held belief that it was a citizen’s duty to take up arms and defend his polis as need arose. Any Greek mercenaries that did exist were generally employed in Persia or Egypt. Mercenaries were also employed in Sicily in significant numbers from an early date. By 481 it seems possible that Gelon, tyrant of Syracuse, maintained an army that included as many as 15,000 mercenaries. They presumably constituted a significant part of the army that won the decisive victory over the Carthaginians at Himera. The most significant event that sparked a major increase in the employment of mercenary troops on mainland Greece was the Peloponnesian War. The Peloponnesian states were the first to employ mercenaries in great numbers. These mercenaries were initially not light-armed troops but hoplites from Arcadia. Athens was slow to hire such troops, largely because of the geographical difficulty in reaching them, but by the end of the war mercenaries of all kinds were finding employment on both sides. The reasons for this change lay in the nature of the war itself. The war was prolonged and almost continuous and there were few large-scale set piece battles fought; most engagements were on a small scale and fought by troops who were relatively lightly equipped and very mobile. Mercenaries were simply better at this kind of combat than heavily armoured hoplites. The hiring of mercenaries was made possible now, and less so earlier, by the relative prosperity of the warring states as compared to earlier in the fifth century.
The end of the Peloponnesian War did not see an ending of the employment of mercenaries in Greece. The peace itself led to a large number of men who had become accustomed to earning their living as hired soldiers suddenly becoming unemployed. This would generally have a destabilizing effect upon any society, but they would not have stayed unemployed for long. The political situation in Greece in the fourth century meant that there were always potential paymasters. Their other great sphere of employment, Persia, was also undergoing change. The central authority of the Persian Empire had begun to weaken. The local governors and satraps grew more independent and ambitious. Their position needed military support, and they found it most readily in Greek mercenaries. It had long been recognized that mercenaries formed a more secure power base for tyrants, rather than citizen soldiers whose loyalty was more open to question if a usurper came along. Greek mercenary infantry in Persian service continually proved themselves more capable than anything that the native Persians were able to achieve, so the great king himself was also forced to hire his own contingents to keep pace with his potentially disloyal satraps. We see this to be true during the reign of Alexander too: the only quality infantry that Darius had at his disposal were the Greek mercenaries. Initially 20,000 strong at the Granicus, they had been reduced to perhaps only 2,000 by the time of Gaugamela. This was because of successive losses at the Granicus and Issus, but probably due to desertion too as it became apparent that Alexander was a more attractive paymaster. The League of Corinth had specifically outlawed a Greek taking up arms against another Greek; this decree had meant little at the outset of the campaign when Persia looked like a good bet for victory. At the time of the battle of Gaugamela in 331, however, Darius found it almost impossible to hire more Greek hoplite mercenaries. This was partly because he was no longer an attractive employer, partly because of the distance from Greece, and partly because Alexander was hiring them in increasing numbers, thus reducing the available pool.