The Battle of Gaugamela is Alexander’s best-known battle, and some have even labeled it his biggest battle since it was a turning point in his conquest of the Persian Empire.
After the inconclusive confrontation with Darius at Issus, both kings knew that another battle was inevitable to establish their supremacy. There was too much at stake, for the King of Persia was not ready to give up his throne. Alexander was most determined to make Persia pay for their repeated invasions and destructions of Greece and for occupying the Greek cities in Asia Minor. As we know, Alexander was in no hurry and made sure to safeguard his rear by taking possession of the coastal cities and territories of the eastern Mediterranean first. After being recognized as Pharaoh in Egypt, he marched back through Syria, ready to meet his opponent in Persia.
Alexander was in Harran (today in southern Turkey) when his scouts reported that the massive Persian army was marching north from Babylon. Allowing his army a few days rest, Alexander then ordered a forced march of 350 km to the Tigris as he aimed to reach the river before any enemy force would stop him from crossing, as he was told by the Persian scouts he had captured.
Darius had had two years to prepare for this decisive battle and may have learned from his mistakes (or, shall we say, misjudgments) at Issus. The King of Kings chose his battlefield with great care and took a position in the vast plain on the eastern bank of the Tigris River, above the Boumelus River (modern Khazir), a tributary of the Great Zab, called Gaugamela. His total force has often been over-estimated, but it is generally accepted that he had about 35,000 cavalry and 250,000 infantry, as well as two hundred Scythian chariots. The Persian forces were six times larger than Alexander’s, and these sheer numbers alone must have caused our conqueror some headaches.
The news of Gaugamela reached Alexander before crossing the Tigris at Abu Dahir (nearly 80 km north of modern Mosul), from where he could follow the Persian Royal Road toward the battlefield. On the fourth day of his Easterly march, some stragglers informed him of the precise position of the Persian army some 25 km away. He decided to allow his troops a four-day rest and to prepare them for further action while he would reconnoiter the layout of the battlefield. Once this was accomplished, he moved his army to a base camp, and the following night he took his fighting forces across the intervening hills, where he rested his men. So far, there had not been any visual contact since a ridge of high ground separated both armies. Only after passing this last ridge Alexander had the first view of his opponent stationed about four miles away. He immediately sent for his staff and commanders to discuss the action plan. They agreed that a careful inspection of the terrain was imperative, and with a group of Companions, Alexander spent a whole day on valuable reconnaissance. Meanwhile, his 47,000 troops were to stay where they were. By the evening, the king summoned and briefed his senior officers again as he had decided to proceed with the attack the following day.
Alexander’s address to his soldiers was quite different from his constant encouragements at Issus, for here, everyone knew how important a victory over the King of Persia was from the onset. Nevertheless, he stressed that every soldier should preserve his discipline in the hour of danger, that all orders must be obeyed promptly, and that all officers, whatever their rank, were to pass their commands to their subordinates without hesitation or delay. Most importantly, Alexander stressed that the conduct of each of his men was crucial to the fate of all. In other words, if everyone did his duty as expected, their success was assured, but if only one man neglected it, the entire army would be in peril. Strong talk! If this is not a pure example of leadership, I don’t know.
Just like at Issus, Alexander ordered his troops to rest and eat; the men had time to discuss their commander’s words and mentally prepare for the upcoming battle. The Macedonians, at least, got more rest than the Persians, who, fearing a night attack, were in a constant state of alert.
For once, we know the exact date on which the battle took place thanks to the recorded eclipse of the moon on September 20 at 9 pm, predicting disaster for the Persian army and good omens for Alexander. The actual fight took place eleven days later, on October 1, 331 BC, and by dawn, Alexander appeared at the head of his men wearing his shining ceremonial armor – ready as he ever could be!
On this vast plain, which had been cleared by the Persians of any obstacle that might hinder their chariots and cavalry, the enemy must have felt pretty confident. Darius had placed his strongest forces on his left wing, the one that would be facing Alexander’s right. These were the best horsemen to be found, the Bactrians and Scythians, with in front of them half of the scythe chariots; 50 more chariots were posted near the Royal Squadron of Darius’ cavalry and another 50 in front of his right wing. Darius took up his position at the center of his line, flanked by his Greek mercenaries, followed by individual cavalry units. Darius’ right was put under the orders of Mazaeus, his most capable general who would be facing Parmenion and his troops.
Alexander, as usual, commanded his right wing with his Cavalry Companions, linked by the 3,000 Shields Bearers to the 10,000-strong phalanx that occupied the center. In front of the cavalry, Alexander had posted his archers, slingers, and javelin throwers, who were his long-range weapons. The Thessalian cavalry was posted on the left under the command of Parmenion. The disposition seems to be the same as the one displayed at Issus, with these exceptions that Alexander added on both flanks a series of block formations, a mixture of heavy cavalry and light infantry in a downward line from his main front and making a near junction with his reserve line of some 20,000 mercenary infantry in the rear posted in parallel with his main forces. It obviously shows that Alexander was well-aware that he would be outflanked by the more numerous Persian troops but at the same time, he was also ready to meet an attack from any direction.
Once his forces were in place, Alexander rode up and down his frontline to lift every man's and every squadron's spirits with a last word of encouragement. Everything depended indeed on the commitment of each and every one of Alexander’s troops to maintain the line and avoid any gap in the formation that could be exploited by the Persians.
With the Persian army strung out far beyond that of Alexander, he immediately started to advance obliquely, leading his Companions forward. Still, as he came closer, he suddenly turned the entire force to the right in a sideways movement. He knew that by doing so, he would expose Parmenion to a more serious encirclement threat, but at the same time, he also knew that if he pressed on beyond the end of the Persian left, the enemy most probably would follow his momentum. Consequently, the Persians would eventually leave a gap in their line, which was precisely what Alexander aimed for.
Darius quickly responded to Alexander’s move by ordering his horsemen to start a flanking maneuver to envelop Alexander and his right wing. The operation seemed successful, but as Alexander stopped his spurt, the Scythian and Bactrian horsemen fighting for Darius rushing straight for Alexander were attacked by his concealed troops, his mercenary cavalry, his infantry flank guards, and several thousands of his veteran mercenaries hidden among them. As the rest of the Persians' left rushed to support the Scythians, the chariots were also commanded forward (while Alexander was still within the leveled ground). Still, these were made useless by a joined action of the javelin throwers and archers. All these movements on the Persian left had created the effect Alexander expected, an opening towards Darius’ chariot at the center.
It makes you wonder how amidst this commotion and heavy dust clouds, Alexander could still order his Companion Cavalry into their customary wedge formation, leading his foot brigades to the offensive against the Persian center. At this point, the Shield Bearers rushed forward, followed on the double by the massive phalanx, probing their sarissas into the enemy lines. Alexander now plunged forward and threw a spear at the Great King (see also: Breathtaking, Alexander the Great at Gaugamela). He missed but killed his charioteer instead. It is probably at this moment that Darius turned his chariot around and fled, closely followed by his Immortals and somewhat shaken Royal guards.
Parmenion, from his end, must have fought a nearly impossible battle in order to keep his squadrons from being encircled and/or dislodged by the Persians under the capable command of Mazaeus. He was outflanked only by a charge of some 3,000 enemy cavalry who rushed through to the Macedonian baggage camp where Queen Mother Sisygambis and her grandchildren were still held in Alexander’s custody. It is unclear whether she refused to accompany her rescuers or if they simply didn’t reach her, as the attackers had not reckoned with Alexander’s line of mercenary reserves that made short work of the enemy forces.
Parmenion being pinned down and hopelessly outflanked left an inevitable gap on the left of the phalanx. A few units of Persian cavalry took their chances and broke the Macedonian line of defense. Their success was short-lived, as the disciplined phalanx soon pushed the Persians back.
Although the battle was not over, the news of Darius’ flight traveled quickly through his ranks and must have demoralized his troops. In the end, it is not clear whether Alexander’s supremacy won the battle or if the Persians lost their drive as their commander-in-chief had fled. With bits and pieces, the Persian army turned its back to the battlefield, and even Mazaeus felt he could not desert his king.
Amazingly and against all odds, Alexander had been able to maintain his line of defense. His men had not let him down!
The details of this battle are very complex. Nobody, not even Alexander, could have a comprehensive overview of how the fight unfolded, and the historical accounts tell only a very partial story. The battlefield was too vast and dusty to make sense of what was going on beyond anyone’s immediate space. The main conclusion is that the battle was won, but with Darius on the run, Alexander could not yet claim his crown as King of Persia.
[Pictures from Oliver Stone's movie Alexander, except the picture of Harran, which is mine]