On 1 October 331, Alexander won his most famous victory against the Persian King Darius III near Gaugamela (close to the modern city of Mosul in Iraq), leading to the fall of the Achaemenid Empire. Known as the Battle of Gaugamela or Arbela, the Macedonian king, vastly outnumbered, defeated the Persian army due to his military genius. As Green put it, “by sheer intuitive genius, he had invented a tactical plan that was to be imitated, centuries afterwards by Malborough at Blenheim and Napoleon at Austerlitz,but which no other general (so far as is known) had hitherto conceived.” Such is the traditional story.
However, Jona Lendering, one of the founders of a school for history teaching, Livius Onderwij, basing his arguments on the Astronomical Diaries from Babylon which reported celestial events and omens before the battle,proposes a new interpretation of this famous battle. In his book Alexander de Grote. De ondergang van het Perzische rijk, he shows that the study of celestial omens really matters for an understanding of the battle of Gaugamela:
On 20 September, immediately after sunset, Darius’ soldiers watched the moon turn blood red and then go dark. […] According to the Persian Magians, an eclipse of the moon was more significant for the king himself than most other omens. The Babylonian Chaldaeans, in their catalogue of prophecies, offered an even less propitious interpretation: “If the moon or the sun are eclipsed and Jupiter is not visible: end of a dominion.” Moreover, according to the systems generally used in prophetic writings, an eclipse on the thirteenth day of the month meant disaster for Babylonia and an eclipse in the month of Ullu meant disaster for Persia. A westerly wind during such an eclipse indicated that the catastrophe was to come from that direction; an easterly wind as the disc of the moon became visible meant the eastern regions were safe. The fact that Saturn was visible gave added force to all these prophecies.
In other words, after the omens of 20 September, a Babylonian astronomer would have known that the end was near for the ruler of Persia and Babylonia and that the cause of his demise would be an enemy from the west. Although the east would provide sanctuary, this was still a demoralising prospect. On another clay tablet we find a similar description of a lunar eclipse, but this time it predicts the fate of the victor rather than the defeated party:
If on the thirteenth or fourteenth of Ullu the moon is eclipsed, the watch passes and the darkness remains, the moon’s features are dark as lapis lazuli, the moon is eclipsed as far as its centre and its western quadrant covered, a westerly wind is blowing, the sky remains dark and the light concealed, then the king’s son will undergo a cleansing ritual in front of the throne, but he will not ascend to the throne. An invader will mount an invasion supported by the rulers of the west; for eight years he will exercise kingship [lacuna]; he will defeat a hostile army; he will find abundance and riches on his path; he will pursue his enemy relentlessly and there will be no end to his good fortune.
[29th Ah tablet of Enuma Anu Enlil; obv. 59-61]
Astrology was not a secret doctrine. We can assume that educated Babylonians in Darius’ army, such as Mazaeus, would have known the fate of their king was sealed. Morale declined visibly, especially when the following day brought word that the Macedonians had made short work of the cavalry unit responsible for laying waste to the land through which Alexander was marching. The Astronomical Diaries record a new omen in the early hours of 23 September: “A meteor flashed. Its light was visible on the ground.”
When daylight came, one of the Persian courtiers taken prisoner during the battle of Issus arrived at Darius’ camp, released in order to bring the great king more bad tidings: his wife Stateira had died in childbirth two days before. Alexander had buried her in accordance with Persian rites.
On the twenty-fourth, Darius sent a messenger to the Macedonian army with a third peace proposal. This time he offered his enemy all the land to the west of the Euphrates and the hand in marriage of one of his daughters who had been captured by Alexander. This proposal shows that the Persian king was keen to avert a battle. His army had been so heavily demoralised by bad omens that he felt forced to make concessions. It was no use. The messenger returned the following day to report that Alexander had rejected his offer.
He also reported that the Macedonians were only forty kilometres away from the Persians that morning and advancing rapidly. In the evening another omen was seen; the Astronomical Diaries refer to it as a “fall of fire”. Exactly what this means is unclear, but it may have been a bolide, a kind of slow meteorite. The phenomenon was seen by the Macedonians as well and it provoked panic. Mazaeus, who had taken up position on a hill between the Macedonian and Persian camps, could see that the enemy was not breaking camp that morning, in fact the Macedonians were starting to reinforce their position with a palisade. Alexander had never approached an enemy so circumspectly. More than ten kilometres separated the two armies.
On the evening of the twenty-sixth there was another fall of fire and Mazaeus informed his king that the Macedonian army remained in its camp. The enemy did not turn out on 27 or 28 September either. No doubt the soldiers made use of the time to sharpen their weapons and to exercise. On the evening of the twenty-ninth Mazaeus saw that the enemy army was on the move and he knew it was time to abandon the hill and join the Persian main force.
A remarkable omission in the sources shows just how great the tension had become. The Macedonian army had to cross a river and pass along a canal that the Assyrian king Sennacherib had laid long before, as a means of supplying Nineveh with clean water. It was one of the greatest engineering achievements of the Ancient World, but it passed unnoticed. At least, the Greek sources, which generally make note of such things, do not refer to it. Neither is there any mention of the nearby ruins of an Assyrian palace.
When the sun rose on 30 September, Darius sent scouts to the far side of the field to study his opponents’ battle formation. It looked similar to their formation at Issus. In the Macedonian centre was the phalanx (under the leadership of Craterus) and on the right wing stood the shield-bearer infantrymen (under the command of Parmenion’s son Nicanor), the companion cavalry (led by Nicanor’s brother Philotas and Alexander) and the light cavalry. On the left wing, commanded as ever by Parmenion, stood the Thessalian and Thracian horsemen, commanded as ever by Parmenion. A second line, invisible to the Persians, consisted of Greek troops and lightly armed soldiers who were to intervene if the Persians attempted a flanking movement.
Alexander and his general staff were also studying the enemy lines, stretched out six kilometres wide in front of them. […] It was an almost moonless night, but not dark, since hundreds of campfires were burning on either side of the plain. Darius did not want a repeat of the battle of Granicus, where the Macedonians had taken advantage of the fact that Persian armies were only allowed to march after performing sacrifices to the rising sun. So he had his men stay awake all night, in battle formation. […]
Our detailed knowledge of events leading up to the battle is mirrored by a lack of information about the engagement itself. We simply have no idea what happened, even though Greek and Roman authors offer detailed descriptions of the advances and manoeuvres that took place on 1 October 331. Their reports amount to saying that Alexander charged at Darius with such energy and terrifying ferocity that he panicked, turned around and thereby put the mass of the Persian army to flight.
The actual course of events was probably rather different. The battleground at Gaugamela was a sandy plain, and the sand they kicked up would have made it impossible for the Macedonians and Persians to see what was happening. After a day of fighting in a dust storm, Alexander’s army emerged in control of the field. No one could say how this had come about, although the Macedonians naturally assumed that their plan of attack had proved successful: an advance by the companion cavalry on the right wing, led by Alexander, while Parmenion’s left wing and the second line took up defensive positions. There is also firm evidence that at some point Mazaeus’ Babylonian horsemen broke through the Macedonian lines, only to take the Macedonian camp instead of attacking the enemy from the rear.
That evening the victors tried to reconstruct what had happened. They put their victory down to the heroic performance of their young king and to Darius’ cowardice. What actually happened lies concealed for ever in the dust clouds of the battlefield, but the Astronomical Diaries do offer some interesting information:
15’ encamped in front of the king. On the 24th, in the morning, the king of the world [erected his] standard […]
16’ Opposite each other they fought and a heavy defeat of the troops [of the king he inflicted…. ]
17’ The king, his troops deserted him and to their cities […]
18’ [to the l]and of the Gutians they fled.
‘King of the world’ is how the Babylonians translated ‘king of Asia’, the title accepted by Alexander. The writer of the Astronomical Diaries had to use this ancient royal title because ‘Asia’ was not a concept he recognised. The striking thing about this fragment is that it says Darius was abandoned by his men and not - as Macedonian propaganda would have it - that he let his men down. By ‘lands in the east’ the writer means Media, where Darius, just as the Chaldaeans had predicted, found sanctuary and could begin raising his third army.
The Babylonian account of the engagement, which was written a few days after the battle, makes sense in the light of what had happened in the days leading up to it. Despite Darius’ meticulous preparations and the fact that his enemy behaved like a puppet in his hands, his soldiers, many of whom had no combat experience at all, were demoralised and ran away. It is only a slight exaggeration to say that the battle of Gaugamela amounted to an attack on a large group of deserters. It wasn’t Alexander’s courage or Darius’ cowardice that decided the fate of the Persian Empire, it was the signs that were seen in the sky.