The 331 BC Battle of Gaugamela and Alexander the Great

The Battle of Gaugamela (Γαυγάμηλα), or Battle of Arbela (Ἄρβηλα), fought on the October 1, 331 BCE, was a turning point in ancient history, marking Alexander the Great's decisive victory over the Persian Empire and solidifying his place as one of history's greatest military tacticians and strategists.

The confrontation was the culmination of escalating hostilities between the ambitious Macedonian king, Alexander III of Macedon who became known as Alexander the Great, (Αλέξανδρος ο Μέγας), and Darius III, the ruler of the vast Persian Empire.

Terry Bailey explains.

The Battle of Gaugamela by Jan Brueghel the Elder, 1602.

The lead-up to Gaugamela

Following his father King Philip II's unification of the Greek city-states and establishment of the League of Corinth, Alexander ascended to the Macedonian throne with aspirations of expansion beyond Greece's borders. His campaign against Persia began in 334 BCE, with Alexander's victories in battles such as Granicus, (Μάχη του Γρανικού), 334 BCE and Issus, (Ἱσσὸς Μάχη), 333 BCE setting the stage for a showdown.

These early successes inspired confidence among Alexander's ranks and raised concerns for Darius, who had underestimated Alexander's prowess. In the wake of the Battle of Issus in 333 BCE, where Alexander had struck a significant blow to the Persian forces, Darius offered peace terms, including a generous ransom for his captured family and large territorial concessions.

Alexander, however, saw himself as Darius's equal and declined the offer, seeking to claim the Persian Empire for himself. Politically, Darius now faced mounting pressure from his subjects to protect the empire's core territories, therefore, moved to consolidate his forces near Gaugamela, a strategically chosen location on the Mesopotamian plains, where he could deploy his army's full strength and exploit the open terrain.

Commanders and armies, strategy and tactics

On the Macedonian side, Alexander commanded a seasoned, highly disciplined army composed of approximately 47,000 troops, including phalanx infantry, elite companion cavalry, and specialised units like archers and highly mobile light infantry. Alexander's forces were strategically flexible and accustomed to his aggressive, calculated tactics. Central to Alexander's strategy was a deep understanding of mobility and the use of oblique formations to outflank larger forces.

Darius III, on the other hand, led a considerably larger force, with estimates ranging from 100,000 to as high as 250,000 troops. The Persian army was a diverse coalition, including cavalry, infantry, chariots equipped with scythes, and a small contingent of war elephants. Darius positioned himself at the centre of his forces, with infantry and heavy cavalry on the flanks and chariots prepared for a decisive charge. His strategy relied on overwhelming Alexander's smaller army with sheer numbers, hoping to use the flat plains of Gaugamela to his advantage.

The battle unfolds, tactics and action

As the battle began, Darius attempted to use his numerical superiority by sending waves of cavalry on both flanks to encircle Alexander's troops. However, Alexander the Great's tactics at the Battle of Gaugamela were masterfully adapted to the open, flat terrain, which should have favoured Darius III's much larger Persian forces. Recognising that a direct, head-on confrontation with such a massive army would be risky, Alexander orchestrated a strategy to exploit his troops' agility, discipline, and skill.

Central to this was his innovative integration of cavalry and infantry, forming a highly flexible, responsive battle line that allowed him to neutralise the Persians' numerical advantage and leverage his own army's strengths. Alexander placed his heavy infantry, the Macedonian phalanx, at the centre of his formation, forming a strong, disciplined core that could hold against Persian attacks.

His famed companion cavalry, led personally by Alexander, was positioned on the right flank, along with other light infantry and cavalry units. This flank was the decisive wing of his army, where Alexander intended to deliver a powerful blow. On the left, under the command of General Parmenion, were additional cavalry and light infantry, tasked with holding their ground against Persian attacks. The integration of cavalry and infantry on both flanks gave the Macedonian army flexibility, allowing Alexander to adapt quickly to Persian moves.

Alexander also employed a tactical feigned retreat and oblique advance, pulling his right-wing cavalry gradually to the right. This manoeuvre drew Persian forces away from their solid front line, stretching them and exposing gaps. When Darius ordered his cavalry to pursue Alexander's right flank, Alexander seized the opportunity.

The Persian line thinned, especially near the centre, where Darius was stationed. At the critical moment, Alexander and his companion cavalry swung sharply to the left, charging through the gap in the Persian centre toward Darius himself. Meanwhile, the Macedonian phalanx advanced, keeping the Persian infantry occupied and preventing them from reinforcing their vulnerable centre.

This coordinated use of cavalry and infantry allowed Alexander to drive a wedge into the Persian army, isolating Darius and forcing him to flee. As the Persian king retreated, the morale of his troops broke, leading to a chaotic withdrawal. Alexander's tactical ingenuity in using a mix of direct engagement and flanking manoeuvres on such open terrain proved decisive, showcasing his ability to adapt and exploit the unique conditions of the battlefield.

Aftermath and legacy

The Battle of Gaugamela signalled the collapse of the Persian Empire, opening the doors for Alexander's forces to capture the key cities of Babylon, Susa, and Persepolis. This victory marked the effective end of Persian power and the beginning of a new era of Hellenistic influence across the former empire. Alexander's victory at Gaugamela became a testament to his strategic brilliance, shaping his legacy as one of history's most formidable conquerors.

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Notes:

Ancient Macedonia

Ancient Macedonia (Μακεδονία), known as Macedon was an ancient kingdom on the periphery of Archaic and Classical Greece, which later became the dominant state of Hellenistic Greece.

The kingdom was founded and initially ruled by the royal Argead dynasty, which was followed by the Antipatrid and Antigonid dynasties. Home to the ancient Macedonians, the earliest kingdom was centred on the northeastern part of the Greek peninsula, and bordered by Epirus to the southwest, Illyria to the northwest, Paeonia to the north, Thrace to the east and Thessaly to the south.

Not to be confused with the Republic of North Macedonia, a landlocked country in Southeast Europe, sharing land borders with Greece to the south, Albania to the west, Bulgaria to the east, Kosovo to the northwest and Serbia to the north.

Alexander the Great's empire

Alexander the Great's empire was one of the largest in the ancient world, stretching from Greece to northwest India.

Extent of the Empire

At its height, Alexander's empire covered approximately 5.2 million square kilometres (2 million square miles), making it the largest empire in the world at the time.

It stretched from Macedonia and Greece in the west, across the Middle East, through Persia (modern-day Iran), and reaching India in the east. The empire also included Egypt and parts of Central Asia.

Key regions and territories conquered

Macedonia and Greece: The empire began here and remained Alexander's cultural and administrative base.

Asia Minor (modern-day Turkey): Alexander moved here after defeating the Persians at the Battle of Granicus, (Μάχη του Γρανικού), 334 BCE.

Persian Empire (modern Iran, Iraq, Syria, and parts of Central Asia): After his decisive victory at the Battle of Gaugamela, (Γαυγάμηλα), in 331 BCE, Alexander claimed the entirety of the Persian Empire, which was the dominant power in the region.

Egypt: He was welcomed in Egypt as a liberator and founded the city of Alexandria.

Mesopotamia and Babylon: These regions became central to his empire after the fall of Persia.

Punjab Region in India: Alexander's easternmost conquests reached the Punjab region, but he did not extend further due to his army's reluctance.

Population and diversity

Alexander's empire was highly diverse, encompassing various cultures, languages, and religions. The empire was home to tens of millions of people, though exact population estimates vary.

Administration and influence

Alexander's conquests helped spread Greek culture, language, and ideas across these regions, influencing them for centuries to come in what became known as the Hellenistic Period. His empire, however, was difficult to govern due to its sheer size, and it began to fragment soon after he died in 323 BCE.

Alexander's empire was significant not only for its size but also for its lasting cultural impact. Greek influence persisted through the Hellenistic kingdoms that succeeded his empire, blending with local cultures across Asia and the Mediterranean.

Phalanx, (φάλαγξ)

One of the most effective and enduring military formations in ancient warfare was that of the Greek phalanx. The age of the phalanx formation may be traced back to Sumeria in the 25th century BCE, through Egypt, and finally appearing in Greek literature through Homer in the 8th century BCE (and since has been generally associated with Greek warfare strategy, the name itself coming from the Greek word for 'finger').

The phalanx formation was a close-rank, dense grouping of soldiers armed with long spears and interlocking shields with the first few ranks of soldiers projecting their spears out over the first rank of shields.

Alexander the Great’s Greatest Victory? The Battle of Gaugamela

Warfare in the Classical World was typified by massed infantry assaults. Iconic is the image of the Greek Hoplite or Roman Legionary marching into battle in impressively synchronized formations to engage in gruesome hand to hand fighting. Cavalry battles tended to be rather rare in comparison. Elements of horse warfare were utilized but mostly limited to reconnaissance and exploiting pursuits of retreating adversaries.

The Battle of Gaugamela, fought in October 331 BCE, is often viewed as Alexander the Great’s greatest victory. It may have involved as many as forty thousand horsemen. It was here, on a level plain somewhere in modern day Iraq that two of antiquity’s greatest superpowers, the Achaemenid Persians and Ancient Macedonians, did battle, culminating in one of the most decisive victories in history.

Brian Hughes explains.

The Battle of Gaugamela by Jan Brueghel the Elder, 1602.

Prelude

Alexander the Third of Macedon, known to history as Alexander the Great, inherited the throne immediately following the assassination of his father, Phillip the Second. Phillip had previously spent several decades conquering the city states of the Greek Peninsula. This was made possible by his shrewd and diplomatic politicking and also the professional Macedonian army in which he almost single handedly reformed from the ground up, subsequently transforming it into the deadliest military force in the Hellenistic World. Alexander not only inherited a tried and tested army but also his father’s ambitious operation to cross the Hellespont and invade the Persian Empire, then the major world power.

Following his initial vanguard, Alexander traversed from Europe and into Asia with the bulk of the Macedonian army and proceeded to score in quick succession a series of audacious victories first at Granicus and then the Battle of Issus where he faced off against the King of the Persian Empire, Darius the Third. It would not be their final confrontation.

In the aftermath of Issus, Alexander chose to not immediately pursue Darius but instead secure his supply lines by marching his army down the Mediterranean coastline through the modern-day countries of Lebanon and Israel and in the process sacking the once thought impregnable fortress city of Tyre in the process. Darius meanwhile retreated into the heart of the Persian Empire in an effort to raise more men in preparation for the next showdown with the Macedonians. Envoys were soon sent to all corners of the Empire not yet taken by Alexander to the various Satraps (Governors) requesting the supply of men. Some even from as faraway as Sogdiana and Bactria, today Uzbekistan and Afghanistan. Alexander would soon turn around and swing east from Egypt and Cyrenaica (Libya) and proceeded through Syria and Mesopotamia. The year was 331 BCE. The battle for the Persian Empire was about to reach its climax.

Preparation

The exact site of the battle is contested to this day. Darius assembled his army at a place called Gaugamela (The Camel’s House) today not far from the city of Mosul. They lay in the direct path in which Alexander and the Macedonian army had planned to take to Babylon. Nestled between the mountains and the Tigris River the plain itself stretched openly for miles granting a considerable advantage to Darius and his numerically superior forces, many of which would fight mounted on horse, chariots, and elephants. Ancient Historians grossly over exaggerated the size of the Persian army, some claiming it to be almost one million. Nonetheless, the army which Darius assembled at Gaugamela was not only enormous (somewhere between fifty and one hundred thousand men) but likewise maintained certain qualitative advantages over the comparatively small Macedonian Army. Intending to make full use of this upper hand Darius ordered his men to clear the chosen spot of battle of any terrain irregularities such as dips and rises so that his cavalry and war machines would have fewer blockers when the time arrived.

Once aware of the location of the Great Kings army, Alexander ordered his men to eschew much of their gear save for their weapons and prepare for a long night march. By dawn the opposing armies were placed only a few miles apart from one another as Alexander convened with his Generals at a council of war. The Macedonian Commanders vehemently argued over how to best negate the considerable Persian supremacy in manpower. Some like Parmenio, one of Phillip’s most trusted Captains had pressed Alexander for a surprise night attack on the Persian camp. This was easier said than done. Battles in and of themselves are exceedingly difficult to coordinate. Thus, a night attack in unfamiliar terrain on this scale in the darkness when it is difficult to distinguish friend from foe was quickly ruled out. Alexander as it would turn out did in fact devise a battle strategy which he believed would win the day. The order was soon given for the army to be fed and properly rested as he himself retired sinking into so heavy a sleep, it has been alleged, that he overslept the next day so confident he was of victory.

Battle

When the day of battle arrived both armies marched under a scorching sun onto the plain and formed up facing one another. It seemed as if the Persian army stretched endlessly as they lined up in two broad columns in which cavalry forces from across the empire with the chariots and war elephants formed the bulk of the center and wings. Darius positioned himself in the center as well, the traditional spot for the King of Kings. Alexander arrayed his men in an almost box-like formation with Parmenio commanding the left flank while the Phalanx and Foot Companions, the nucleus of the mighty Macedonian army formed up in the center. On the right Alexander took personal command along with his elite Hetaroi or Companion Cavalry in addition to other crack forces.

Alexander was determined to open the board with the first move. He proceeded to ride steadily to the right giving the notion of riding around the left flank of the Persian army. Darius was stunned. Did Alexander really intend to envelop his gargantuan force? Having faced this young conqueror before and being aware of his ability to defy the odds and achieve seemingly miraculous victories Darius chose to leave nothing to chance. He ordered Bessus the Satrap of Bactria to shadow Alexander with his lethal Cavalry from Bactria and Central Asia. While this was happening the Macedonian Phalanx in the center began to steadily creep toward the main Persian line. It was difficult for the Phalanx to maintain order over such a distance as the Persian chariots began to charge forward over the very ground leveled only days ago. Darius then committed the bulk of his forces against the increasingly vulnerable Macedonian left flank.

Shockingly, the chariots appeared to inflict minimal damage against the battle-hardened infantrymen who rehearsed tactics for dealing with such weapons. Meanwhile, on the Macedonian left, the situation became more and more desperate. Parmenio proceeded to maintain some semblance of order forming his line into an inverted horseshoe of sorts. This was meant to bog down Persian forces to buy time for Alexander and his companions to initiate a bold maneuver.

Having overextended the Persian horsemen Alexander abruptly wheeled back with his elite cadre and headed for Darius and the Persian center at full speed. Tying up the cavalry force sent to intercept him far to the right, it must have been inconceivable to Darius to see Alexander spearheading a charge and plunging straight towards him through a storm of shield, spears, and sword. Alas it was too much to handle. As his right and center columns began to fold Darius ordered his chariot to turn around and flee. The demoralized Persians seeing this quickly followed suit as most of the army began to collapse. Except on the Macedonian left. By now Parmenio’s small and beleaguered force was facing certain annihilation as the Persian swarmed past his flank nearly surrounding him and even raiding the Macedonian encampment. Alexander was then confronted with a dilemma. He could pursue Darius thus sealing the fate of the Persian Empire but lose his army in the process or come to the aid of his General. He chose the latter and brought to bear the full power of the Macedonian Cavalry slamming into the Persians in an awesome battle where thousands of men and horses fought savagely until it became too much for the hard-pressed Persians who then fled.

Aftermath

Gaugamela was a complete victory for Alexander and the Macedonians. The Persian army was utterly defeated as Alexander marched to Babylon and the heartland of the Persian Empire unopposed. The wealth and strategic advantage that would accompany these acquisitions would prove monumental as Alexander turned his gaze further eastward - it seemed virtually nothing could satisfy his ravenous ambition for glory and further conquest. Darius retreated deep into the vastness of his crippled empire, attempting in vain to raise further troops so that he might reclaim his throne. It would ultimately be to no avail as Bessus, who commanded the Persian left at Gaugamela led a coup betraying and assassinating Darius and then proclaimed himself Emperor in his stead. Alexander would eventually track down Bessus before executing him as he continued to push east only turning around several years later at the stubborn behest of his homesick army who would not follow him any further. By now Alexander had claimed the entirety of the Persian Empire and ruled from the Balkans to the border of India.

Alexander would likewise meet a premature death in June 323 BCE at the age of thirty-two. It is a mystery to this day as to how he passed, however.

Few in history have acquired the epitaph “The Great.” Alexander had proven himself to be one of the best military leaders in world history winning countless battles under all kinds of circumstances. Gaugamela remains his greatest victory in both its daring and outcome, so wrestling of control of the Persian Empire.

What do you think of the Battle of Gaugamela? Let us know below.

Sources

Alexander The Great, Philip Freeman: Simon and Schuster

Carnage and Culture Landmark Battles and The Rise of Western Culture, Victor Davis Hanson Random House INC.

Gaugamela (331 BCE) - Livius