Battle of Gaugamela

The Battle of Gaugamela (Γαυγάμηλα) took place in 331 BC between Alexander the Great of Macedonia  and Darius III of Achaemenid Persia. The battle, which is also called the Battle of Arbela, resulted in a massive victory for the Macedonians and led to the fall of the Achaemenid Persian Empire.

Location
Darius chose (or smoothed out, depending on accounts) a flat plain where he could deploy his numerically superior forces; however, the location of Gaugamela has not been established definitively. Supposedly, the battle was held near a hill in the form of a camel's hump, hence the name etymology: Tel Gomel or Tel Gahmal, which translates as "Mount Camel" in Hebrew. Others translate the name as "camel's stall" (Plutarch: "camel's house", in his Life of Alexander), and associate the place with a settlement. The most commonly accepted opinion about the location is (36.36°N, 43.25°W), east of Mosul in modern-day northern Iraq – suggested by Sir Aurel Stein in 1938 (see his Limes Report, pp. 127–1)

Background
During the two years after the Battle of Issus, Alexander proceeded to occupy the Mediterranean coast and Egypt. He then advanced from Syria against the heart of the Persian empire. Alexander crossed both the Euphrates and the Tigris rivers without any opposition. Darius was building up a massive army, drawing men from the far reaches of his empire. He planned to use numbers to crush Alexander, and according to some contemporary historians he gathered around 100,000 men. Darius also picked a flat plain for a battlefield so Alexander would have no advantages in terrain, and allowing Darius to use his vast horde more effectively.

Time of attack
On the eve of battle Alexander's generals were of the view that to counter the overwhelming advantage in numbers of the Persians a night attack should be launched. Alexander is said to have dismissed the notion explaining that as he was no ordinary general he would not act like one. As it turned out Alexander's timing of battle was right. Darius, fearing a night attack, kept his army awake and on alert for the whole night, while Alexander's were more rested. As a matter of fact, though, Darius was right to be afraid; Alexander had attacked immediately both in the Battle of the Granicus and the Battle of Issus.

Modern estimates
Some modern scholars suggest that Darius III's army was no larger than 50,000 because of the logistics of fielding more than 50,000 soldiers in battle being extremely difficult at the time. However, it is possible that the Persian army could have numbered over 100,000 men. One estimate is that there were 25,000 peltasts, 10,000 Immortals, 2,000 Greek hoplites, 1,000 Bactrians, and 40,000 cavalry, 200 scythed chariots, and 15 war elephants. Hans Delbruck however estimates the number of Persian Cavalry at 12,000 because of management issues and Persian infantry (peltast) less than that of the Macedonian heavy infantry and the Greek Mercenary at 8,000.

Warry estimates a total size of 91,000. Welman estimates a total size of 90,000. Delbrück (1978) estimates a total size of 52,000. Engels (1920) and Green (1990) also estimate the total size of Darius' army to be no larger than 100,000 at Gaugamela.

Ancient sources
According to Arrian, Darius's force numbered 40,000 cavalry and 1,000,000 infantry, ; Diodorus Siculus put it at 200,000 cavalry and 800,000 infantry, ; Plutarch put it at 1,000,000 troops (without a breakdown in composition), while according to Curtius Rufus it consisted of 45,000 cavalry and 200,000 infantry. Furthermore according to Arrian, Diodorus, and Curtius, Darius had 200 chariots while Arrian mentions 15 war elephants. Included in Darius's infantry were about 2,000 Greek mercenary hoplites.

While Darius had a significant advantage in numbers, most of his troops were of a lower quality than Alexander's. Alexander's pezhetairoi were armed with a six-meter spear, the sarissa. The main Persian infantry was poorly trained and equipped in comparison to Alexander's pezhetairoi and hoplites. The only respectable infantry Darius had were his 10,000 Greek hoplites and his personal bodyguard, the 10,000 Persian Immortals. The Greek mercenaries fought as an Argos phalanx, armed with a heavier shield but with spears no longer than three meters, while the spears of the Immortals were 2 meters long. Among his other troops the most heavily armed were the Armenians who were armed the Greek way, probably as an Argos phalanx. The rest of his contingents were much more lightly armed; the main weapon of the Achaemenid army historically was the bow and arrow.

Modern estimates
Alexander commanded a force from his kingdom of Macedon, Thracian allies and the Corinthian League that, according to Arrian, the most reliable historian of Alexander (who is believed to be relying on the work of the eye-witness Ptolemy), numbered 7,000 cavalry and 40,000 infantry. Most historians agree that the Macedonian army consisted of 31,000 heavy infantry including the Greek hoplites in reserve, with an additional 9,000 light infantry consisting mainly of Peltasts with some Archers. The size of the Macedonian mounted units was about 7,000.

Initial dispositions
The battle began with the Persians already present at the battlefield. Darius had recruited the finest cavalry from his Eastern satrapies and from an allied Scythian tribe. Darius also deployed scythed chariots for which he had prepared cleared terrain in front of his troops. He also had 15 Indian elephants supported by Indian chariots, although these seemingly played no role in the battle. Before the battle, Darius ordered bushes and vegetation removed from the battlefield, to maximize the chariots' effectiveness.



Darius placed himself in the center with his best infantry as was the tradition among Persian kings. He was surrounded by, on his right, the Carian cavalry, Greek mercenaries, and the Persian horse guards. In the right-center he placed the Persian foot guards (Apple Bearers/Immortals to the Greeks), the Indian Cavalry and his Mardian archers.

On both flanks were the cavalry. Bessus commanded the left flank with the Bactrians, Dahae cavalry, Arachosian cavalry, Persian cavalry, Susian cavalry, Cadusian cavalry, and Scythians. Chariots were placed in front with a small group of Bactrians. Mazaeus commanded the right flank with the Syrian, Median, Mesopotamian, Parthian, Sacian, Tapurian, Hyrcanian, Caucasian Albanian, Sacesinian, Cappadocian, and Armenian cavalry. The Cappadocians and Armenians were stationed in front of the other cavalry units, and led the attack. The Albanian and Sacesinian cavalry were sent around to flank the Macedonian left.

The Macedonians were divided into two, with the right side of the army falling under the direct command of Alexander, and the left to Parmenion. Alexander fought with his Companion cavalry. With it were the Paionian, and Macedonian light cavalry. The mercenary cavalry was divided into two groups, with the veterans being stationed on the flank of the right, and the rest being put in front of the Agrians and Macedonian archers which were stationed next to the phalanx. Parmenion was stationed on the left with the Thessalian, Greek mercenary, and Thracian cavalry units. There they were to pull off a holding maneuver while Alexander landed the decisive blow from the right.

On the right-center of the formation were Cretan mercenaries. Behind them was a group of Thessalian cavalry under Phillip, and Achaian mercenaries. To their right was another part of the allied Greek cavalry. From there came the phalanx, which was placed into a double-line. Outnumbered over 5:1 in cavalry, with their line surpassed by over a mile, it seemed inevitable that the Macedonians would be flanked by the Persians. The second line were given orders to deal with any flanking units should the situation arise. This second line consisted of mostly mercenaries.

Beginning of the battle
Alexander began by ordering his infantry to march in phalanx formation towards the center of the enemy line. The Macedonians advanced with the wings echeloned back at 45 degree angles to lure the Persian cavalry to attack. While the phalanxes battled the Persian infantry, Darius sent a large part of his cavalry and some of his regular infantry to attack Parmenion's forces on the left.

During the battle Alexander used an unusual strategy which has been duplicated only a few times throughout history. His plan was to draw as much of the Persian cavalry as possible to the flanks. The purpose of this was to create a gap within the enemy line where a decisive blow could then be struck at Darius in the center. This required almost perfect timing and maneuvering, and the Great King himself to act first. Alexander would force Darius to attack (as they would soon move off the prepared ground) though Darius did not want to be the first to attack after seeing what happened at Issus against a similar formation. In the end Darius's hand was forced, and he attacked.

Darius now launched his chariots, some of which were intercepted by the Agrianians (javelin throwers). It is said that the Macedonian army had trained for a new tactic to counter these devastating chariots if they ran into their ranks. The first lines would step aside, opening a gap. The horse would refuse to run into the lances of the front ranks, and enter the "mouse trap", only to be stopped by the lances of the rear ranks. The charioteers and their horses could then be killed at leisure. The chariots were rendered useless.

Alexander's decisive attack
As the Persians moved farther and farther to the Macedonian flanks in their attack, Alexander slowly filtered in his rear-guard. Alexander disengaged his Companions, and prepared for the decisive attack on the Persians. Leading the way, he formed his units into a giant wedge, with him leading the charge. Behind them were the guards brigade along with any phalanx battalions he could withdraw from the battle. These were follow-up light troops. Alexander took most of his cavalry and moved parallel to Darius's front lines, heading off of the prepared battlefield. In response, Darius ordered his cavalry in the front lines to block Alexander's force. Unbeknownst to Darius, Alexander hid a force of peltasts (light infantry armed with slings, javelins, and shortbows) behind his horsemen and Alexander slowly sent his force into an angle, heading toward the Persian host, until finally a gap opened between Bessus's left and Darius's center and Alexander sent in his cavalry force to drive down the gap in the Persian line in a wedge formation. At the same time, the peltasts engaged the cavalry, so as to keep them from riding back to engage Alexander's charging cavalry. The infantry at the center were still fighting the phalanxes, hindering any attempts to counter Alexander's charge.



This large wedge then smashed right into the weakened Persian center, taking out Darius's royal guard, and the Greek mercenaries. Bessus on the left, now cut off from Darius, and fearing he would be struck with this wedge, began to pull back his forces. Darius was in danger of himself being cut off, and the widely held modern view is that he now broke and ran, with the rest of his army following him. This is based on Arrian's account (Anabasis 3.14):


 * "For a short time there ensued a hand-to-hand fight; but when the Macedonian cavalry, commanded by Alexander himself, pressed on vigorously, thrusting themselves against the Persians and striking their faces with their spears, and when the Macedonian phalanx in dense array and bristling with long pikes had also made an attack upon them, all things together appeared full of terror to Darius, who had already long been in a state of fear, so that he was the first to turn and flee."

A less common view is that Darius's army was already broken when Darius ran, and is supported by an astronomical diary from Babylon written within days of the battle:


 * The twenty-fourth [day of the lunar month], in the morning, the king of the world [i.e., Alexander] [erected his] standard [lacuna]. Opposite each other they fought and a heavy defeat of the troops [of the king he inflicted]. The king [i.e., Darius], his troops deserted him and to their cities [they went]. They fled to the land of the Guti.

The left flank
Alexander could have pursued Darius at this point. However, he received desperate messages from Parmenion (an event which would later be used by Callisthenes and others to discredit Parmenion) on the left. Alexander was faced with the choice of pursuing Darius, but losing his army, or going back to the left flank to aid Parmenion and preserve his forces. In the end, he made the decision to help Parmenion, and follow Darius later.

While holding on the left, a gap had also opened up between the left and center of the Macedonian line. The Persian and Indian cavalry units stationed in the center with Darius broke through. Instead of taking the phalanx or Parmenion in the rear, however, they continued on towards the camp to loot. They also tried to rescue Queen Mother Sisygambis but she refused to go with them. On their way back, the Indians slew over 60 of the Companion cavalry.

Meanwhile, as the center and Darius broke, Mazaeus also began to pull his forces back as Bessus had. However, unlike on the left with Bessus, the Persians soon fell into disorder as the Thessalians and other cavalry units charged forward at their fleeing enemy.

Aftermath
After the battle, Parmenion rounded up the Persian baggage train while Alexander and his own bodyguard chased after Darius in hopes of catching up. As at Issus, substantial amounts of loot were gained following the battle, with 4,000 talents captured, as well as the King's personal chariot and bow. The war elephants were also captured. In all, it was a disastrous defeat for the Persians, and possibly one of Alexander's finest victories.

Darius had managed to escape the battle with a small core of his forces remaining intact. The Bactrian cavalry and Bessus managed to catch up with him, as did some of the survivors of the Royal Guard and 2,000 Greek mercenaries.

At this point, the Persian Empire was divided into two halves – East and West. On his escape, Darius gave a speech to what remained of his army. He planned to head further East, and raise another army to face Alexander while he and the Macedonians headed to Babylon. At the same time he dispatched letters to his Eastern satrapies asking them to remain loyal.

The satrapies, however, had other intentions. Bessus murdered Darius, before fleeing eastwards. Alexander would pursue Bessus, eventually capturing and executing him the following year. The majority of the existing satraps were to give their loyalty to Alexander, and be allowed to keep their positions. However, the Persian Empire is traditionally considered to have fallen with the death of Darius.

Filmography
Alexander has had many movies dedicated to his life, but the last one, Alexander, describes the battle quite faithfully, except for minor details as the elephants, missing in the movie.

Ancient sources

 * The Anabasis of Alexander: The Battle of Gaugamela (Book 3, 7~16) By Arrian, Translated by E.J.Chinnock
 * Alexander the Great: An annotated list of primary sources from Livius.org
 * Wiki Classical Dictionary, extant sources and fragmentary and lost sources
 * Plutarch, Life of Alexander (in English)
 * Justin, Epitome of the Philippic History of Pompeius Trogus (in English)
 * Plutarch, Of the Fortune or Virtue of Alexander the Great (in English)
 * Quintus Curtius Rufus, Histories of Alexander (in Latin)

Modern sources

 * Delbrück, Hans (1920). History of the Art of War. University of Nebraska Press. Reprint edition, 1990. Translated by Walter, J. Renfroe. 4 Volumes.
 * Dodge, Theodore Ayrault (1890-1907). History of the Art of War: Alexander
 * Engels, Donald W. (1978). Alexander the Great and the Logistics of the Macedonian Army. Berkeley/Los Angeles/London.
 * Fox, Robin Lane (1973). Alexander the Great. London: Allen Lane.
 * Fuller, J. F. C. A Military History of the Western World. Three Volumes. New York: Da Capo Press, Inc., 1987 and 1988.
 * v. 1. From the earliest times to the Battle of Lepanto; ISBN 0-306-80304-6: pp. 87 to 114 (Alexander the Great).
 * Green, Peter. Alexander of Macedon 356-323 B.C.
 * Green, Peter (1990). Alexander to Actium; The Historical Evolution of the Hellenistic Age. Berkeley/Los Angeles.
 * History of the Greek Nation volume Δ, Ekdotiki Athinon, Athens 1973
 * Moerbeek, Martijn (1997). The battle of Gaugamela, 331 BC. Universiteit Twente.
 * De Santis, Marc G. “At The Crossroads of Conquest.” Military Heritage . December 2001. Volume 3, No. 3: 46-55, 97 (Alexander the Great, his military, his strategy at the Battle of Gaugamela and his defeat of Darius making Alexander the King of Kings).
 * Van der Spek, R.J. "Darius III, Alexander the Great and Babylonian Scholarship." in: W. Henkelman, A. Kuhrt eds., A Persian Perspective. Essays in Memory of Heleen Sancisi-Weerdenburg. Achaemenid History XIII (Leiden: Nederlands Instituut voor het Nabije Oosten, 2003) 289-342.
 * Warry, J. (1998). Warfare in the Classical World. ISBN 1-84065-004-4.
 * Welman, Nick. Battles (Major) and Army. Fontys University.