This battle is not hypothetical. Between 334 and 331 BC, Alexander the Great led a Macedonian army of around 40,000 men into the largest empire the world had yet seen and destroyed it in three great battles. Here is how a small kingdom from northern Greece brought down the Persian Achaemenid Empire, and why it happened.
The Macedonians: Who They Were
For most of Greek history, Macedon was a backward kingdom on the northern edge of the Greek world. That changed with Philip II, who took the throne in 359 BC. Philip had spent part of his youth as a hostage in Thebes, where he studied the tactics of the great general Epaminondas. As king, he built Greece's first truly professional standing army, paid it with gold from Macedonian mines, and used it to dominate Greece, finally crushing Athens and Thebes at Chaeronea in 338 BC.
When Philip was assassinated in 336 BC, his 20-year-old son Alexander inherited the army and his father's plan to invade Persia. Alexander had been taught by Aristotle and had already commanded the cavalry at Chaeronea.
The Persian Empire: Who They Were
The Achaemenid Empire, founded by Cyrus the Great around 550 BC, stretched from Egypt and Anatolia to the borders of India. It was rich, well run, with a famous road system and royal messengers, and tolerant of the many peoples it ruled. Its king, Darius III, could call on troops from dozens of provinces: Persian and Median infantry, the royal guard known as the Immortals, superb cavalry from Bactria and Scythia, and thousands of Greek mercenaries.
Persia's problem was not size or wealth, but cohesion. Its armies were huge collections of different peoples with different weapons, languages and loyalties, and everything depended on the king.
Weapons and Armour
- Macedonians: the heart of the army was the phalanx of pezhetairoi (foot companions) armed with the sarissa, a pike around 5 to 6 metres long held in both hands. The first five ranks' pike points stuck out in front of the formation, creating a wall of iron. Elite hypaspists linked the phalanx to the cavalry. The decisive arm was the Companion cavalry, heavy horsemen with lances who charged in a wedge formation, led personally by Alexander.
- Persians: infantry carried spears, bows and wicker shields and wore little heavy armour, apart from the Greek mercenary hoplites. The cavalry was excellent and often heavily armoured. At Gaugamela, Darius also deployed around 200 scythed chariots and 15 war elephants.
The Three Great Battles
Granicus (334 BC)
Soon after crossing into Asia, Alexander found a Persian army of local governors waiting on the far bank of the River Granicus. He charged across with his cavalry, was nearly killed in the fighting (his friend Cleitus saved his life), and broke the Persian horse. The Greek mercenaries in Persian service were then surrounded and cut down.
Issus (333 BC)
Darius himself arrived with a much larger army but chose to fight on a narrow coastal plain in southern Anatolia, where his numbers could not be fully used. Alexander led the Companions straight at the Persian left, then turned towards Darius, who fled. The Persian army collapsed, and Darius's mother, wife and daughters were captured.
Gaugamela (331 BC)
For the final showdown Darius chose a wide, flat plain in northern Iraq and even levelled the ground for his chariots. Alexander had about 47,000 men. Ancient sources give Darius impossible figures of up to a million; modern historians suggest somewhere between 50,000 and 120,000, but agree he had far more cavalry.
Alexander's plan was brilliant and risky. He advanced at an angle to the right, dragging the Persian left wing along with him. Darius's scythed chariots charged, but the Macedonian light infantry opened lanes, let them through and killed the crews. As the Persian line stretched, a gap opened. Alexander formed the Companions into a wedge and drove straight through it towards Darius. For the second time, Darius fled, and his army disintegrated. Meanwhile, Parmenion on the Macedonian left had barely held on against the Persian right.
Why the Macedonians Won
- Combined arms: the phalanx pinned the enemy in place while the cavalry struck the decisive blow. Each part of the army had a clear job.
- Professionalism: Philip's soldiers had drilled together for years. The Persian army was assembled from provinces for each campaign.
- Leadership: Alexander led from the front and read battles brilliantly. Darius stayed in the centre, and when he fled, the whole army lost heart.
- Choice of ground: even at Gaugamela, on Darius's chosen ground, Alexander's manoeuvre neutralised the Persian advantages.
Aftermath
After Gaugamela, Alexander took Babylon, Susa and the royal capital of Persepolis, which was burned in 330 BC. Darius was murdered that same year by his own satrap Bessus. Alexander pushed on to Central Asia and India before dying in Babylon in 323 BC, aged 32. His empire split apart among his generals, but Greek culture spread across the Middle East for centuries afterwards.
Verdict: Who Wins?
History has already answered this one: the Macedonians, decisively, in three straight battles. The community agrees, with the Macedonians holding one of the biggest leads on the site. The more interesting question might be whether Persia could have won with a different king or a better strategy, such as the plan of the Greek mercenary general Memnon to avoid battle and burn the land ahead of Alexander. What do you think? Vote on the homepage.
Sources and Further Reading
- Arrian, The Campaigns of Alexander (Anabasis)
- Plutarch, Life of Alexander
- Robin Lane Fox, Alexander the Great
- Pierre Briant, From Cyrus to Alexander: A History of the Persian Empire