Alexander’s Macedonian Army

Lachlan McColl, Dickson College, 2007

The Macedonian army of Alexander the Great was a wonder of military organisation, tactical superiority, and battlefield discipline. Before Philip II, Alexander’s father, became king, Macedonia was an insignificant kingdom in northern Greece. When Philip became king in the mid third century BCE, it was bankrupt and threatened by invasion from all sides. Philip built it up into a powerful nation by resupplying its coffers, reinforcing its borders and beginning the creation of a vast and powerful army, paving the way for his son Alexander’s rise to glory.

When he became king in 356, Alexander remodelled the army to make use of a variety of units, from light javelin-men to ultra-heavy cavalry. He built on the military advances of his father Philip II who had reorganised the army and implemented a strict training regime. The success of the army was guaranteed by the masterful use and coordination of both the invincible phalanx and the devastating heavy cavalry. It gained a reputation for unstoppable assaults and impenetrable defences. Alexander used a combination of fear, surprise, speed, brute force and the manoeuvrability of his cavalry to sap away the morale of his enemies, and his own personal bravery to boost that of his own warriors. Alexander led this army from Macedonia to Egypt; then through Persia and even into India. Throughout the entire campaign, Alexander masterfully utilised his heavy infantry, fast cavalry, superior morale, lightning speed, and an unbreakable determination to win, and, as a result, never once lost a battle.

The Macedonian phalanx developed by Philip II was different to the earlier Greek hoplite formation. The soldiers in Philip’s new phalanx used a longer double-handed spear, a smaller shield (suspended from the left shoulder) and lighter armour. This reduction in protection made each individual soldier cheaper to equip, therefore allowing for larger numbers to be recruited. (Sage 1996) When more lightly equipped, each soldier occupied less space than did the hoplites, allowing more spears to be presented to an enemy in any given area. The spear used was the long sarissa. Theophrastus states the length of the sarissa in his History of Plants “The height of the male tree is approximately twelve cubits (12 cubits=approximately 18 feet), the length of the longest sarissa (Theophrastus 3.12.2), whereas Polybius claims that it was exactly 14 cubits. (Polybius, 18.29.1-30.4) Regardless of this discrepancy, it was certainly much longer than the 7-10 foot spear used by earlier hoplites. This great length allowed for every soldier in the first 5 ranks to participate in the fight and meant that the phalanx could effectively outnumber any enemy force on the charge, or present a wall of 5 pikes ahead of every man in the front rank when defending. The ranks that could not reach the fighting:

…hold their sarissas slanting in the air above the shoulders of the men in front and so protect the whole formation by keeping off missiles by means of a thick cover formed by the sarissas.” (Polybius, 18.29.1-30.4)

It was this unique ability that allowed the Macedonian phalanx to best almost any opponent, and at the very least lock an enemy in a long struggle while the cavalry could attack their flanks at any time.

The cavalry that performed this task were the two elite troops of Alexander’s army, Alexander’s personal guard, the Companion cavalry, and the auxiliary Thessalian cavalry. These two units were the Greek equivalents of battle tanks: fast, manoeuvrable, terrifying and unstoppable on the charge. The Companions were not only the greatest soldiers in the army, but also tactical and financial advisers to Alexander off the field. “The right wing consisted of the Companion cavalry with the royal squadron posted at the front” ( Anabasis 3.11.8). Often on the left of Alexander’s formations, the Thessalian cavalry were a unit of heavy cavalry from the northern kingdom of Thessaly, who acknowledged the Macedonian king as their supreme ruler. Alexander’s heavy cavalry fought with long cornel wood lances and sabres, allowing them to deliver a devastating charge before engaging in close-quarters fighting if the enemy did not break. The heavy armour consisted of a corslet (breastplate), open-faced helmets, boots and sometimes leather greaves. Their main aim, however, was to obliterate small sections of the enemy with one charge, avoiding prolonged combat, as they were usually heavily outnumbered. Arrian says that the wedge formation “makes it easy to cut through an enemy formation” (Arrian, Tactics 16.6-7) and was used by the Macedonian cavalry. Once they made a breach in the enemy’s line they were able to ride through and move unhindered around the back of the army, forcing the enemy to either relocate frontline units to counter them or dispatch their reserves if they had any. This forced the enemy to react rather than act and allowed Alexander to dictate their battle plan to them.

Speed was an important part of his strategy. Alexander needed to be able to quickly position and reposition his heavy cavalry throughout the battle to both respond to enemy movements and to create obstacles to undermine the enemy’s battle plan and force them to react to him rather than move freely of their own accord. Speed also created terror amongst the enemy, as Alexander’s cavalry were so efficient at manoeuvring about the battlefield that they could appear almost anywhere to threaten the flanks of units or attack from behind. On several occasions, most notably when fighting the Persians, they even managed to get into a position in which to assault the enemy’s leader. At the battle of Gaugamela Alexander, facing the Persian king Darius, engaged the numerous Persian infantry with the heavy hoplites in the centre of his army, used his Thessalian cavalry to temporarily hold off the Persian cavalry on his left flank, and charged with his elite companion cavalry into the Persian left flank. He broke straight through and circled inward to attack Darius’ personal guard with the support of the phalanx.

He led them forward at full speed and with a loud shout went straight at Darius himself…thrusting at their faces with their spears, and the Macedonian phalanx…now closely attacking them. All this appeared equally terrible to Darius, who was already in panic. He was the first to turn and flee.” (Anabasis 3.11.3-15.6)

Upon seeing their king disappear in his chariot, the Persian army instantly broke and fled. Alexander used speed to attack Darius’ guard, and by defeating that one unit, won the battle.

Morale was everything to Alexander’s battle tactics. His army was designed to terrify the enemy troops by focusing on small sections of their army and obliterating them utterly, then closing in for the final decisive blow that would sweep away any remaining resistance with a terrifying shout of “Alalai” and an oncoming wall of spear tips. In a document regarding Alexander’s actions against the Triballians in 335BCE, Arrian highlighted an example of this:

When Alexander had drawn them out of the wood he ordered Philotas to take the Companion cavalry of Upper Macedonia and charge their right wing where they had come furthest forward in their rush forward.” (Anabasis 1.2.4-5)

This tactic was vital to Alexander’s success. He was usually outnumbered and was in constant danger of being overwhelmed if the enemy’s ranks held firm. If he could break the morale of unengaged units with a concentrated charge of heavy cavalry into their flank, they would often flee before his infantry even reached them. The lighter cavalry and infantry could then be brought up to pursue the retreating enemy, stopping them from regrouping and killing or capturing any who could not escape.

Fully understanding the importance of strong morale and bravery to the success of an army in the field, Alexander constantly made sure that his troops had an abundance of both. He did this by showing personal bravery and by leading all the assaults himself. He was often the first over the walls in a siege, or in the front rank of a cavalry charge. This boosted the morale of his troops and instilled in them a sense of devotion to their leader. This devotion boosted their bravery, as they were determined to keep pace with, and protect, their general. Alexander ensured by the position of the units in his army that each man was protected by another and was never in danger of being attacked where they could not defend. This helped to maintain their morale and fighting spirit, and avoided any splitting up of the ranks during a battle.

Alexander’s army was a masterpiece of military strategy, organisation and training. His troops were, as a rule, much more efficient killers than any of his opponents, his battle plans were devastatingly effective in all circumstances, and he was able to maintain control of his army even in the heat of battle. His units worked cohesively and could, when aiding each other by fulfilling their designated roles, overcome any obstacle.

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Further Reading

Arrian, Anabasis of Alexander, in Michael M. Sage 1996, Warfare in Ancient Greece: A Sourcebook, Routledge, London
Polybius, Histories, in Michael M. Sage 1996, Warfare in Ancient Greece: A Sourcebook, Routledge, London

Theophrastus, History of Plants, in Michael M. Sage 1996, Warfare in Ancient Greece: A Sourcebook, Routledge, London

J.V. Muir, M.A. and E.R.A.Sewter, M.A. 1965, Alexander the Great, Oxford University Press, London

Author unknown, Published December 2005, Ancient Macedonian Army>>Alexander the Great Articles, Viewed 14th August 2007

Saner van Dorst, last updated late 2005, Army of Alexander the Great, viewed 16th August 2007 < (note: original web page was deleted, copy may be found at:>

E.L. Skip Knox, Alexander the Great, viewed 19th August 2007, <>

Author unknown, Published December 1998, Macedonia, viewed 19th August 2007 <>

"Philip II, king of Macedon." The Columbia Electronic Encyclopedia.
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