Gandhara/Tech Tree

There were six types of troops in the Mauryan imperial army: the ksatriya, or troops of the hereditary warrior class who formed the spine of the professional army; mercenaries and freebooters hired as individuals seeking military adventure; troops provided by corporations or guilds; troops supplied by subordinate allies; deserters from the enemy; and wild forest and hill tribesmen used in the same manner as the French and British used Native American tribes in their wars in North America. The troops of the corporations are little understood and may have been units maintained by guilds to guard their caravan routes and trade stations. Such units were later found in the armies of medieval Europe. The imperial armies were not conscript armies. In Vedic times, war fighting was the responsibility of all members of the tribe. By the time of the Mauryas, whatever sort of conscription had once existed earlier had disappeared, and the imperial armies comprised professional warrior aristocrats and other professionals fed, equipped, trained, paid, and otherwise maintained at great cost to the state.
The Mauryan army was quite large. Classical sources (Pliny) state that the size of the army of the last Nanda king was 200,000 infantry, 20,000 cavalry, 2,000 chariots, and 3,000 elephants when it was overwhelmed by Chandragupta’s force of 600,000 infantry, 30,000 cavalry, and 9,000 elephants. When Alexander confronted Porus on the banks of the Hydaspes, he faced an army of 30,000 foot, 4,000 cavalry, 300 chariots, and 200 war elephants, an army of considerable size to be deployed by a minor king of a minor state in the Jhelum region. Less than a year later, Alexander confronted the army of the Malavas state, another minor regional entity, and faced an army of 80,000 well-equipped infantry, 10,000 cavalry, and 800 chariots. Even accounting for the exaggeration common in ancient accounts, it is by no means unlikely that these armies were this large. The population of India during this period was somewhere between 120,000,000 and 180,000,000 people. Even excluding the lower social orders, the Mauryan empire possessed an enormous manpower pool. Moreover, India was rich in gold and metals and the skills to produce weapons in great quantities in state armories. The Ganges plain and other areas farther north were excellent for breeding mounts for the cavalry. Whatever the true size of the imperial armies, they are all recorded as smaller than those said to have existed during the later medieval and Muslim periods of Indian history.
The tactical organization of the Mauryan army may have been influenced somewhat by the Chinese innovation of combining several combat arms within a single tactical unit and training it to fight together, employing their arms in concert. Indian armies of this period had within them a basic unit called the patti, a mixed platoon comprising one elephant carrying three archers or spearman and a mahout, three horse cavalrymen armed with javelins, round buckler, and spear, and five infantry soldiers armed with shield and broadsword or bow. This twelve-man unit when assembled in three units formed a senamukha, or “company.” Three of these formed together comprised a gulma, or “battalion.” Units were added in multiples of three, forming an aksauhini, or “army,” comprised of 21,870 patti. Sources also speak of military units formed around multiples of ten, and there were no doubt units of single arms that could be employed individually or in concert with other arms. The Arthasastra mentions a unit called the samavyuha, or “battle array,” that was about the size of a Roman legion (5,000 men). This unit comprised five subunits joined together, each subunit containing 45 chariots, 45 elephants, 225 cavalry, and 675 infantrymen each. It goes without saying that managing such units in battle required a high degree of tactical sophistication.
The military equipment of the Mauryan imperial army was essentially the same as it had been for the previous 500 years. The Indian bow was made of bamboo and was between five and six feet long and fi red a long cane arrow with a metal or bone tip. Nearchus, the Cretan chronicler who accompanied Alexander into India, noted that the bowman had to rest the bow on the ground and steady it with his left foot in order to draw it full length. The arrow fi red from the bamboo bow could penetrate any armor. At the Hydaspes the battle took place over muddy ground, which prevented the archers from steadying their bows in this manner, rendering them useless. The composite bow, or sarnga, was also used but probably far less so and not by cavalry. When Alexander’s Asian cavalry archers at the Hydaspes attacked the Indian cavalry with bow and arrow, the Indian cavalry took heavy losses and had no means of returning fi re. It is unlikely that the Indian cavalry ever became proficient with the bow, relying completely on the lance and javelin, the weapons of light cavalry. If the Mauryan army possessed heavy cavalry, they appear to have done so in small numbers.
Infantrymen carried a long, narrow shield made of raw ox hide stretched over a wooden or wicker frame that protected almost the entire body, unlike the small round buckler carried by the cavalry. Armed with spear, bow, and javelin, the infantry tended mostly to be of the light variety. Heavy infantry carried the nistrimsa, or long, two-handed slashing sword, while others were armed with iron maces, dagger axes, battle axes, and clubs. A special long lance, the tomara, was carried by infantry mounted on the backs of elephants and was used to counter any enemy infantry that had fought its way through the elephant’s infantry screen to attack the animal itself. What evidence we have suggests that from Vedic times until the coming of the Greeks, only slight use was made of body armor, and most of that was of the leather or textile variety. With Alexander’s invasion, however, the use of metal and lamellar armor became more widespread, as did the use of scale plate armor for horses and elephants. The helmet did not come into wide use until well after the Common Era, and for most of the ancient period the Indian soldier relied mostly on the thick folds of his turban to protect his head.
By the Mauryan period the Indians possessed most of the ancient world’s siege and artillery equipment, including catapults, ballistas, battering rams, and other siege engines. A distinguishing characteristic of Indian siege and artillery practice was a heavy reliance on incendiary devices, such as fire arrows, pitch pots, and fireballs. There was even a manual instructing how to equip birds and monkeys with the ability to carry fire inside buildings and onto rooftops. This was not surprising in a country whose military fortifications and buildings were made mostly of wood. Fire was such a constant threat to Indian towns that thousands of water containers and buckets were required to be kept full and placed outside dwellings at all times to extinguish fi res. All citizens were required by law to assist in fighting fi res, and it was required that people sleep in the room nearest the street exit to escape fi re more easily and to be quickly available to help in fighting them. So serious was the concern for fi re that the punishment for arson was death by burning alive.
The Arthasastra declares that a good army can march two yojanas a day and that a bad army can only manage one. This is a rate of march for an effective army of about ten miles a day, considerably below what the armies of the Near East could manage during the same period. It is likely that the Mauryan army followed the old Vedic practice of agreeing with the enemy as to the location of a battlefield in advance. Under these conditions, tactical surprise was likely to have been a rare event. Much of the advice offered by the Arthasastra, at least from the tactical perspective, seems to be of the same variety as that proffered by Sun-Tsu, more a set of maxims designed to make the commander think than a set of rules to be applied in certain circumstances. That is why, to the Western mind, such maxims often appear obvious. Hints of a tactical system appear, however, in the suggestion that whether the attack is from the center, right, or left, it should always be led by the strongest troops. The weakest troops are to be kept in reserve. But the reserve is very important. The king should always station himself with the reserve to exploit any enemy failure, and a king should “never fight without a reserve.”