Finding any further pursuit of Darius hopeless, Alexander now directed his march towards Babylon. At a little distance from the city the greater part of the population came out to meet him, headed by their priests and magistrates, tendering their submission and bearing with them magnificent presents. Alexander then made his triumphant entry into Babylon, riding in a chariot at the head of his army. The streets were strewed with flowers, incense smoked on either hand on silver altars, and the priests celebrated his entry with hymns. Nor was this a mere display of a compulsory obedience. Under the Persian sway the Chaldaean religion had been oppressed and persecuted; the temple of Belus had been destroyed and still lay in ruins; and both priests and people consequently rejoiced at the downfall of a dynasty from which they had suffered so much wrong. Alexander observed here the same politic conduct which he had adopted in Egypt. He caused the ruined temples to be restored, and proposed to offer personally, but under the direction of the priests, a sacrifice to Belus. Alexander contemplated making Babylon the capital of his future empire. His army was rewarded with a large donative from the Persian treasury; and after being allowed to indulge for some time in the luxury of Babylon, was again put in motion, towards the middle of November, for Susa. It was there that the Persian treasures were chiefly accumulated, and Alexander had despatched one of his generals to take possession of the city immediately after the battle of Arbela. It was surrendered without a blow by the satrap Abulites. The treasure found there amounted to 40,000 talents in gold and silver bullion, and 9000 in gold Darics. But among all these riches the interest of the Greeks must have been excited in a lively manner by the discovery of the spoils carried off from Greece by Xerxes. Among them were the bronze statues of Harmodius and Aristogiton, which Alexander now sent back to Athens, and which were long afterwards preserved in the Ceramicus.

At Susa Alexander received reinforcements of about 15,000 men from Greece. He then directed his march south-eastwards towards Persepolis. His road lay through the mountainous territory of the Uxians, who refused him a passage unless he paid the usual tribute which they were in the habit of extorting even from the Persian kings. But Alexander routed them with great slaughter. He then advanced rapidly to Persepolis, whose magnificent ruins still attest its ancient splendour. It was the real capital of the Persian kings, though they generally resided at Susa during the winter, and at Ecbatana in summer. The treasure found there exceeded that both of Babylon and Susa, and is said to have amounted to 120,000 talents or nearly 30,000,000l. sterling. It was here that Alexander is related to have committed an act of senseless folly, by firing with his own hand the ancient and magnificent palace of the Persian kings; of which the most charitable version is that he committed the act when heated with wine at the instigation of Thais, an Athenian courtezan. By some writers, however, the story is altogether disbelieved, and the real destruction of Persepolis referred to the Mahommedan epoch. Whilst at Persepolis, Alexander visited the tomb of Cyrus, the founder of the Persian monarchy, which was situated at a little distance, at a city called Pasargadae.

Thus in between three and four years after crossing the Hellespont Alexander had established himself on the Persian throne. But Darius was not yet in his power. After the battle of Arbela that monarch had fled to Ecbatana. It was not till about four months after the battle of Arbela, and consequently early in 330, that Alexander quitted Persepolis to resume the pursuit of Darius. On approaching Ecbatana he learned that the Persian monarch had already fled with the little army which still adhered to him. Alexander, with his main body, then pursued Darius through Media by forced marches and reached Rhagae, a distance of three hundred miles from Ecbatana, in eleven days. Such was the rapidity of the march that many men and horses died of fatigue. At Rhagae he heard that Darius had already passed the defile called the "Caspian Gates," leading into the Bactrian provinces; and, as that pass was fifty miles distant, urgent pursuit was evidently useless. He therefore allowed his troops five days' rest, and then resumed his march. Soon after passing the Gates he learned that Darius had been seized and loaded with chains by his own satrap Bessus, who entertained the design of establishing himself in Bactria as an independent sovereign. This intelligence stimulated Alexander to make still further haste with part of his cavalry and a chosen body of foot. On the fourth day he succeeded in overtaking the fugitives with his cavalry, having been obliged to leave the infantry behind, with directions to follow more at leisure. The enemy, who did not know his real strength, were struck with consternation at his appearance, and fled precipitately. Bessus and his adherents now endeavoured to persuade Darius to fly with them, and provided a fleet horse for that purpose. But the Persian monarch, who had already experienced the generosity of Alexander in the treatment of his captive family, preferred to fall into his hands, whereupon the conspirators mortally wounded him in the chariot in which they kept him confined, and then took to flight. Darius expired before Alexander could come up, who threw his own cloak over the body. He then ordered him to be magnificently buried in the tomb of his ancestors, and provided for the fitting education of his children.

The next three years were employed by Alexander in subduing Hyrcania, Drangiana, Bactria, and Sogdiana, and the other northern provinces of the Persian empire. In these distant regions he founded several cities, one of which in Aria, called after him (Alexandria Ariorum), is still, under the name of HERAT, one of the chief cities in central Asia. Alexander's stay in Prophthasia, the capital of Drangiana, was signalized by a supposed conspiracy against his life, formed by Philotas, the son of Parmenio. Alexander had long entertained suspicions of Philotas. But the immediate subject of accusation against him was that he had not revealed a conspiracy which was reported to be forming against Alexander's life, and which he had deemed too contemptible to notice. He was consequently suspected of being implicated in it; and on being put to the torture he not only confessed his own guilt in his agonies, but also implicated his father. Philotas was executed, and an order was sent to Ecbatana, where Parmenio then was, directing that veteran general to be put to death. A letter, purporting to be from his son, was handed to him; and whilst the old man was engaged in reading it, Polydamus, his intimate friend, together with some others of Alexander's principal officers, fell upon and slew him. His head was carried to Alexander.

Meantime Bessus had assumed the royal dignity in Bactria; but upon Alexander's approach he fled across the Oxus into Sogdiana. Early in the summer of 329 Alexander followed him across the Oxus; and shortly afterwards Bessus was betrayed by two of his own officers into the hands of Alexander. Bessus was carried to Zariaspa, the capital of Bactria, where he was brought before a Persian court, and put to death in a cruel and barbarous manner.

Alexander even crossed the river Jaxartes (SIR), and defeated the Scythians. Sogdiana alone of the northern provinces offered any serious resistance to his arms. Accordingly in 328 he again crossed the Oxus. He divided his army into five bodies, ordering them to scour the country in different directions. With the troops under his own command he marched against the fortress called the Sogdian Rock, seated on an isolated hill, so precipitous as to be deemed inaccessible, and so well supplied with provisions as to defy a blockade. The summons to surrender was treated with derision by the commander, who inquired whether the Macedonians had wings? But a small body of Macedonians having succeeded in scaling some heights which overhung the fortress, the garrison became so alarmed that they immediately surrendered. To this place a Bactrian named Oxyartes, an adherent of Bessus, had sent his daughters for safety. One of them, named Roxana, was of surpassing beauty, and Alexander made her the partner of his throne (B.C. 328).

At Maracanda (now SAMARCAND) he appointed his friend Clitus satrap of Bactria. On the eve of the parting of the two friends Alexander celebrated a festival in honour of the Dioscuri (Castor and Pollux), though the day was sacred to Dionysus (Bacchus). The banquet was attended by several parasites and literary flatterers, who magnified the praises of Alexander with extravagant and nauseous flattery. Clitus, whom wine had released from all prudent reserve, sternly rebuked their fulsome adulation; and, as the conversation turned on the comparative merits of the exploits of Alexander and his father Philip, he did not hesitate to prefer the exploits of the latter. He reminded Alexander of his former services, and, stretching forth his hand, exclaimed, "It was this hand Alexander, which saved your life at the battle of the Granicus!" The king, who was also flushed with wine, was so enraged by these remarks, that he rushed at Clitus with the intention of killing him on the spot, but he was held back by his friends, whilst Clitus was at the same time hurried out of the room. Alexander, however, was no sooner released than, snatching a spear, he sprang to the door, and meeting Clitus, who was returning in equal fury to brave his anger, ran him through the body. But when the deed was done he was seized with repentance and remorse. He flung himself on his couch and remained for three whole days in an agony of grief, refusing all sustenance, and calling on the names of Clitus and of his sister Lanice who had been his nurse. It was not till his bodily strength began to fail through protracted abstinence that he at last became more composed, and consented to listen to the consolations of his friends, and the words of the soothsayers, who ascribed the murder of Clitus to a temporary frenzy with which Dionysus had visited him as a punishment for neglecting the celebration of his festival.

After reducing Sogdiana, Alexander returned into Bactria in 327, and began to prepare far his projected expedition into India. While he was thus employed a plot was formed against his life by the royal pages, incited by Hermolaus, one of their number, who had been punished with stripes for anticipating the king during a hunting party in slaying a wild boar. Hermolaus and his associates, among whom was Callisthenes, a pupil of Aristotle, were first tortured, and then put to death. It seems certain that a conspiracy existed; but no less certain that the growing pride and haughtiness of Alexander were gradually alienating from him the hearts of his followers.

Alexander did not leave Bactria till late in the spring. He crossed the Indus by a bridge of boats near Taxila, the present ATTOCK, where the river is about 1000 feet broad, and very deep. He now found himself in the district at present called the PENJ-AB (or the FIVE RIVERS). Taxiles, the sovereign of the district, at once surrendered Taxila, his capital and joined the Macedonian force with 5000 men. Hence Alexander proceeded with little resistance to the river Haydaspes (BEHUT or JELUM). On the opposite bank, Porus, a powerful Indian king, prepared to dispute his progress with a numerous and well-appointed force. Alexander, however, by a skilful stratagem conveyed his army safely across the river. An obstinate battle then ensued. In the army of Porus were many elephants, the sight and smell of which frightened the horses of Alexander's cavalry. But these unwieldy animals ultimately proved as dangerous to the Indians as to the Greeks; for when driven into a narrow space they became unmanageable, and created great confusion in the ranks of Porus. By a few vigorous charges the Indians were completely routed, with the loss of 12,000 slain and 9000 prisoners. Among the latter was Porus himself, who was conducted into the presence of Alexander. The courage which he had displayed in the battle had excited the admiration of the Macedonian king. Mounted on an enormous elephant, he retreated leisurely when the day was lost, and long rejected every summons to surrender; till at length, overcome by thirst and fatigue, he permitted himself to be taken. Even in this situation Porus still retained his majestic bearing, the effect of which was increased by the extraordinary height of his stature. On Alexander's inquiring how he wished to be treated, he replied, "Like a king." "And have you no other request?" asked Alexander. "No," answered Porus; "everything is comprehended in the word king." Struck by his magnanimity, Alexander not only restored him to his dominions, but also considerably enlarged them; seeking by these means to retain him as an obedient and faithful vassal.

Alexander rested a month on the banks of the Hydaspes, where he celebrated his victory by games and sacrifices, and founded two towns one of which he named Nicaea, and the other Bucephala, in honour of his gallant charger Bucephalus, which is said to have died there. He then overran the whole of the PENJ-AB, as far as the Hyphasis (GHARRA), its southern boundary. Upon reaching this river, the army, worn out by fatigues and dangers, positively refused to proceed any farther; although Alexander passionately desired to attack a monarch still more powerful than Porus, whose dominions lay beyond the Hyphasis. All his attempts to induce his soldiers to proceed proving ineffectual, he returned to the Hydaspes, when he ordered part of his army to descend the river on its opposite banks; whilst he himself at the head of 8000 men, embarked on board a fleet of about 2000 vessels, which he had ordered to be prepared with the view of sailing down the Indus to its mouth.