Alexander’s invasion of India had begun in the winter of 327–326 BCE. Over the preceding twenty months he had destroyed Darius, the last Achaemenid emperor, and proclaimed himself king of kings in his stead. He had hunted down and executed the rebel Bactrian satrap Bessos, who had killed Darius. Wherever he set foot he had planted new cities named after himself, including Alexandria in Arachiosa (modern Kandahar, more properly Iskandahar), Alexandria under Kaukasos (modern Begram, south of the Hindu Kush), and Alexandria Eschate, or ‘Furthest’ (in modern Tajikistan). But it was not enough, and his thoughts had turned to India – according to the historian Herodotus, the most populous nation in the known world and the richest.
No army had ever been so well educated as that which marched to Alexander’s drum, particularly those cavalry officers known as the Companions who commanded the royal wing and the eight other squadrons of horse, and the infantry commanders known as the Shield-Bearers who spearheaded the right phalanx of Alexander’s army. Some had been friends of Alexander since childhood and had attended the school at Mieza at which the philosopher Aristotle of Stagira had presided over Alexander’s education, tutoring him from the age of thirteen in philosophy, morals, logic, science, mathematics, medicine and art. At Mieza Alexander had learned that what distinguished Greeks and Macedonians from other men was the spirit of enquiry. But his education had been cut short when his father King Philip went away to wage war against Byzantium. From that time onwards Alexander had been too busy either defending or enlarging Philip’s kingdom to give much thought to Aristotelian ethics.
There was nothing morally uplifting about Alexander’s extraordinary advance into Asia but it did at least accord with Aristotle’s assertion that ‘All men by nature desire to know’. No less than sixteen of those who accompanied Alexander are known to have written accounts of that extraordinary journey eastwards. None of these eyewitness accounts have survived in the original but enough material was still accessible in the days of late republican and imperial Rome for Greek and Roman historians to plunder them for their own versions of Alexander’s eastern adventure, of which five survived to be read by Sir William Jones, together providing a detailed, if contradictory, account of Alexander’s invasion of India.
Having made his decision to press on, Alexander had sent envoys to all the local rulers calling on them to submit to his authority. Those whose territories lay in the plains had had ample time to reflect on Alexander’s relentless advance across Asia and responded with alacrity. There were even protestations of the warmest friendship from an Indian king whom the Greeks came to know as Omphis of Taxila, whose territories extended east from the River Indus to the River Hydaspes (the modern Jhelum). So eager was King Omphis to show his goodwill that he crossed the Indus to meet Alexander, bringing offerings that included twenty-five war elephants – no mean gift, for these were the battle tanks of the day.
However, the mountain tribes of the Aspasioi and Assakenoi – names probably derived from Sanskrit aswa, or ‘horse’, and aswa-senis, ‘horse-fighters’, thus ‘horse-people’, and ‘horse-warriors’ – refused to submit. Alexander thereupon divided his army, sending one force down through the defile known today as the Khyber Pass to the winter capital of Gandhara at Peukelaotis (Pushkalavati, now Charsadda, just above the confluences of Swat River and Kabul River) while he himself led the best of his troops on a more northerly route into the mountains.
The winter campaign that followed was swift and brutal in the Alexandrian manner. The first Aspasian town that lay across Alexander’s path failed to surrender and every inhabitant was put to the sword; the second held out only briefly before opening its gates. The Greeks renamed this second city Nysa, because it was overlooked by an ivy- and vine-covered mountain that reminded them of the mountain sacred to their god Dionysus. The historians Arrian, Justin and Curtius all tell the same story, which was that Nysa stood at the foot of a mountain called Meros, the summit of which was then occupied by Alexander’s forces for ten days of bacchanalian revelry. With his men thoroughly rested, Alexander continued his mountain campaign, which ended with his assault on the great rock of Aornos, a supposedly impregnable mountain that was said to have defeated Heracles himself. Here the last of the Aspasioi and Assakenoi had gathered to make a final stand.
The name given to this great massif may come from the Greek aornos, ‘birdless’, but more probably derives from the Sanskrit awara, meaning ‘stockade’; thus the Fortress Mountain. Described by Arrian as ‘a mighty mass of rock … said to have a circuit of about 200 stadia [1 stadium = 607 feet] and at its lowest elevation a height of 11 stadia’, the Aornos massif overlooked the plains of Gandhara and the River Indus at its most northerly crossing-point. It meant that Aornos had to be taken before Alexander could contemplate going any further east.
Alexander duly set about besieging the Fortress Mountain, building up an earthwork to bridge a ravine on one side while a party led by Ptolemy, one of the commanders of Alexander’s Shield-Bearers, set about scaling the cliffs at a second point. By the third day the earthwork was complete and Alexander himself led the main assault, resulting in a rout and a massacre. ‘Alexander thus became master of the rock,’ declares Arrian. ‘He sacrificed upon it and built a fort, giving the command of its garrison to Sisikottos, who long before had in Bactria deserted from the Indians to Bessos, but after Alexander had conquered the Bactrian land served in his army, and showed himself a man worthy of confidence.’
The Indian deserter deputed to govern Aornos ‘Greekified’ by Arrian as Sisikottos is Romanised by Curtius into Sisocostus. The two are clearly one and the same, for the Roman historian ends his account of the taking of Aornos in much the same way as the Greek: ‘Upon the rock the king erected altars dedicated to Minerva and Victory. To the guides who had shown the way … he honourably paid the stipulated recompense … The defence of the rock and the country surrounding was entrusted to Sisocostus.’
All the surviving accounts record that Indian mercenaries were employed by the Aspasioi, Assakenoi and other mountain peoples and showed no scruples in switching sides. Alexander made extensive use of their military skills before coming to see them as a threat, at which point he disposed of them so ruthlessly as to lead Plutarch to accuse him of an act of treachery: ‘As the Indian mercenary troops, consisting, as they did, of the best soldiers to be found in the country, flocked to the cities which he attacked, he thus incurred serious losses, and accordingly concluded a treaty of peace with them; but afterwards, as they were going away, set upon them while they were on the road, and killed them all.’
Sisikottos/Sisocostus was one such Indian mercenary, initially fighting for the Persian satrap Bessos in Bactria against Alexander before switching sides to soldier for the Greeks, where his qualities of leadership evidently recommended him to Alexander as ‘a man worthy of confidence’. The significance of his name was missed by Sir William Jones, as it was by many students of Indo-Greek history who came after Jones.
With Mount Aornos taken and his line of supply secured, Alexander was able to reunite his forces and cross the Indus, where he made the customary sacrificial offerings before marching on to Taxila, a ‘great and flourishing city, the greatest indeed of all the cities which lay between the river Indus and the Hydaspes’. Here he and his Macedonians were made welcome by King Omphis and his people, the Indian king showering upon Alexander gifts that included another fifty-six elephants, a number of sheep of extraordinary size, three thousand bulls, quantities of corn, gold crowns and eighty talents of coined silver. So gratified was Alexander by the Taxilan king’s generosity that he returned his gifts with thanks and added ‘a thousand talents from the spoils which he carried, along with many banqueting vessels of gold and silver, a vast quantity of Persian drapery, and thirty chargers from his own stalls’ – an act of statesmanship that, according to Quintus, caused ‘the deepest offence to his own friends’.