In May 326 BCE, the unbeaten Macedonian army invades the Punjab region of the Indian subcontinent. Despite the pouring rain, Alexander, King of Macedon, Asia, and Persia, stands on the western bank of the Hydaspes River, as he considered how to overcome the next daunting challenge waiting for him on the other side of the river. His last great battle, against a formidable Indian King and his vast army was just about to happen.

During the spring of 330 BCE, with the troublesome crossing of the Zagros Mountains behind, the Macedonian army reaches its final destination, the city of Persepolis. Alexander quickly discovered, that a good part of the royal treasury had been moved to Ecbatana in Media, where defeated king Darius struggled to form yet another army. The Macedonian king had taken the majority of the most important Achaemenid cities and decided to celebrate the Persian New Year in the just captured capital. He requested local aristocracy to pledge allegiance to his rule, but only a few nobles together with freshly appointed satraps attended the festivities. It became obvious, that despite naming himself King of Asia, Alexander’s claim to the Persian throne needed to be beyond reproach. The only way to do that was by killing Darius, who still formally remained, King of Persia. Prior to his departure for Ecbatana, Alexander burned and looted Persepolis, wanting to avenge the Persian capture of Athens 150 years earlier.

The pursuit had begun. The Macedonians arrived at Ecbatana in June, only to learn that Darius was no longer there. The Persian King was well informed regarding his enemy’s movement and left the city some days earlier, marching northeast with his treasuries and followers, hoping to reach the yet unconquered easternmost part of the empire. Still, there were subjects willing to obey royal authority, but upon learning of the Macedonian chase, Darius’ ranks began to thin out due to desertions. His courtier’s lead by Bessus eventually arrested him, satrap of Bactria, who hoped that handing the Persian king over to the Macedonians would avert the conquest of their eastern provinces. Yet Alexander turned down the disloyal satraps’ offer. It was probably a better choice regarding his claim to the Persian throne, as Bessus then killed Darius. While the Macedonians and Persians buried Darius in Persepolis with full honors, Bessus crowned himself as the new Persian King under the name Artaxerxes. Bessus expected the Macedonians to return to Europe, just as other reasonable invaders would do, but it was not the case for Alexander.

Another extraordinary campaign began and in the matter of one year, Alexander crossed and subjugated the vast plains of Central Asia. Around that time, the first serious fractures started to appear in the Macedonian war machine. After the conquest of Persepolis and death of Darius, many regular soldiers expected Alexander to return home, as five long years had passed since they crossed the Hellespont to fight the Persians. Moreover, it looked like their beloved King had changed. He often demanded godlike treatment, took over many of the Persian customs and surrounded himself with Persian advisors. He also became gradually more suspicious. When Alexander discovered a plot against his life, he put one of his commanders Philotas on trial and had him killed, despite the lack of sufficient evidence.  It was a troublesome deed, as Philotas was the firstborn son of Parmenion, Alexander’s trusted general and second-in-command. The execution of the son meant that the father must die too. Alexander hastily sent couriers back west with clear orders. Death met the old general in Ecbatana, where he guarded the royal treasury and supervised reinforcements. Parmenion remained loyal to the last.

In the meantime, Alexander’s troops were about to cross the Hindu Kush range, one of the last obstacles on their way to attack Bessus’ domain. It was late winter, and Bessus did not believe that Alexander would risk marching through the snowy mountain passes, yet it soon became clear that he once again underestimated the Macedonian King. Alexander managed to cross the mountains unopposed with minor losses to labor, and completely surprised Bessus. Soon, the Macedonians acquired Bactria, forcing the usurper to flee north of the river Oxus. However, nothing could stop Alexander. Despite Persian efforts to disrupt his progress, he marched through the desert, crossed the river and directly confronted Bessus’ force. Finally, Bessus’ own men imprisoned the usurper because they all feared the rage of the Macedonian King and they handed over Bessus to Alexander. He was then tortured and crucified. Now, Alexander could crown himself as the unopposed king of Persia. He spent over a year quelling the unrests in his newly conquered lands. To calm the tribes inhabiting the eastern satrapies, Alexander married Bactrian princess, Roxana. With the northeast border secured, he turned his eyes on to populous and fertile lands of the Indian subcontinent. Probably the primary motivation for the new Indian campaign was Alexander’s impertinence and uncontrollable desire for conquest, as the possible gains were dubious and the risk of failure was significant.

Regardless, the Macedonian armies entered Punjab in late 327 BC, and soon reached the lands inhabited by the Taxile people. Their king greeted Alexander who soon expected all neighboring states to pledge allegiance to the new Macedonian overlord. Indeed, many local rulers bent the knee to the exotic invaders. However, there was one chieftain on the other side of the Hydaspes river, who refused to surrender. King Porus of the Pauravians was a noble and courageous leader with a significant army and solid border in the form of a wide river. Of course, his refusal was very unacceptable to Alexander, and soon the Macedonian troops reached the western bank of the Hydaspes. King Porus was already there, and he was guarding against the possible crossing. It was May, and he could easily stall. Melting snow in the Himalayas together with upcoming monsoon rains could render the river almost impassable for many months. Alexander knew this too, and tried to act as quickly as possible. Closer examination of the river convinced him, that a direct crossing with the enemy guarding the other side was an easy way to lose his army.

Alexander had to find another solution to this problem. Porus’ troops patiently shadowed the Macedonian movements, who sought an opportunity to cross the river. In fact, this was just a feint to let the Indian guard down. Upon finding a suitable ford 30 kilometers upstream, he gathered his best units and during the stormy night transported them across the river. Porus could not believe the rumors about the Macedonian crossing, and sent a 2,000 strong mounted detachment under his son to investigate. Young Porus encountered Alexander completing the crossing, and decided to repel them immediately. Yet the Greeks, who after a short skirmish routed the Indian patrol, easily stopped his brave charge. The young prince did not survive the fight. Though he failed to stop the crossing, Porus at least learned that the enemy was now on the same side of the river, and began deploying his troops.

The Macedonian army was considerably larger, yet the majority of the troops were still on the west bank of Hydaspes, thus the Indian army heavily outnumbered Alexander’s detachments, which crossed the river. However, superior Macedonian training, discipline, and experience partially diminished their numerical advantage. Yet the Indians employed more than 100 formidable war elephants, which posed a serious threat to the Macedonian units, as it was the first time they had to face such an extraordinary enemy on the battlefield. The battle started with the attack of Scythian hired horse archers, who tried to harass the elephants. Shortly, Companion cavalry lead by Alexander struck the Indian left flank. He tried to avoid the enemy’s elephants because such a threat was new to Macedonian horses. Macedonian horses feared elephants and the horses often refused to cooperate. The sarissa phalanx reached the Indian line in the center and engaged the elephant units.

Although the Macedonians lengthened their sarissa spears in order to fight the elephants prior to the battle, they still had a tough time engaging these powerful beasts. The war elephant units managed to penetrate the Macedonian line here and there. King Porus saw that his left flank was clearly losing, thus he sent chariots and cavalry from the right to aid the collapsing left. This was a clear signal for Coenus, commander of the remaining cavalry units. He quickly moved his mounted troops and rushed through the Indian right flank, encircled them and attacked the left flank from the rear. The Macedonians killed some of the elephant drivers in the center, and the panicked animals fled, trampling their own infantry. Seeing that the enemy was slowly gaining an upper hand in the center and especially on the left flank, a couple of infantry units started to waver and flee the battlefield. However, they quickly realized, that leftover Macedonian troops under Craterus had crossed the river and attacked the running Indians. Just after slaughtering the fleeing units, Craterus moved forward and engaged the Indian rear.  King Porus, still fighting on his elephant, was aware that he had lost the battle, yet refused to surrender.

Finally, the Macedonians captured Porus, and the remaining part of his army avoided slaughter. The casualties on the Indian side were significant. The Macedonians killed almost their entire cavalry and a good part of their infantry, while the Macedonians lost around 1,000 soldiers, mostly in the center. Alexander asked King Porus, who was a humongous warrior over seven feet tall, how he wished to be treated. He replied, “Treat me like a king would treat another king”. Porus’ attitude impressed Alexander and appointed him as the new satrap of Punjab. Although the Battle of Hydaspes River was the last major battle of the Macedonian king, he realized that he fought against a capable opponent, and his history continued.

PRIMARY SOURCES: Diodorus Siculus (90-30 BC). Bibliotheca Historica. Quintus Curtius Rufus (60-70 AD). Historiae Alexandri Magni. Plutarch (75 AD). The Life of Alexander the Great, Parallel Lives. Arrian (early 2nd century AD). Metz Epitome. Baz Battles Videos on the Battle of the Hydaspes. The Great Courses Plus.