After crossing the Hellespont from homeland Greece to Asia Minor – the Western half of the mighty Persian Empire – with an army of approximately forty-thousand men, Alexander gathered his men and headed for the Aegean coast and Persian naval bases. It was extremely important that he captured or took out these coastal cities otherwise he ran the risk of the Persians attacking Greece by sea whilst he was on campaign.
As his forces advanced into the Persian lands, they were scouted by Memnon of Rhodes, who suggested that the Persian soldiers retreat, burning the farms behind them so that the Macedonians would starve. However, this proposal did not go down well with the citizens, and the noblemen were forced to make a pitched stand at the Granicus River, which flowed West into the Aegean.
Despite the season allowing the river to be relatively shallow and not a dangerous drowning hazard, it still had “steep” and “abrupt” banks, making it a strategic obstacle and a protective barrier for the Persians who had set up their army behind it. Sources disagree, but they most likely had about 15,000 cavalry, 10,000 infantry and a rearguard unit of Greek (traitor) mercenaries which numbered about 8,000. They were probably outnumbered by the approaching Macedonians.
On the other hand, the Greek army was fairly well prepared, apart from food, which they knew would run short within long. The first battle would have to be a success if the campaign was to continue appropriately. Alexander took control of the right wing of his army, a flank comprised of mixed units, but mainly Elite and Companion cavalry. Numbering about 3,000 horses, this was expected by the Persians to be the main blow force, but it was merely a distraction used by the Greeks to trick the enemy.
Heavy infantry phalanx formations made up the centre of the army in a long, impenetrable line. Towards the climax of the battle, the size and density of these units would have a powerful psychological effect upon the Persians.
Palmenion controlled the left wing with 2,000 cavalry and suggested that Alexander prepare his soldiers for a crossing of the Granicus River the following morning. However, the king disagreed and decided to lead his right-wing Companion cavalry across the water immediately. Attempting to charge the far right of the Persians, his horses began to outflank the enemy’s left wing.
This caused them to draw forces away from the centre to deal with the threat of encirclement by the Greeks.
The units arriving from the Persian centre put up a desperate fight, but were lightly armed compared to the Greeks and were gradually forced back. Spotting an opportunity to dominate the Persians’ left flank, he ordered another charge by the remainder of his cavalry, the Elite Horsemen. Heading extremely far right and just about circling them, these horses posed a serious threat to the Persians, who immediately diverted cavalry from their centre to form a defensive line on their wing to defend against these invaders.
Consequently, the Persian centre was now considerably weaker and was a great target for an attack by Alexander’s mighty sarissa phalanx units. As they marched forwards, across the river and onto a wide field, the enemy, who, realising that they didn’t stand a chance against the professionally organised Greeks, began to turn and flee. As the main part of the Persian army disintegrated, Alexander turned the direction of his cavalry on the Persian left flank and headed towards the middle. Once this part had fallen apart, all that remained were the Greek mercenaries, that were considered traitors to be fighting for the Persians. Instantly, they were surrounded, and with their cries for mercy ringing out, were slaughtered brutally. Alexander lost two hundred cavalry and a hundred infantry, compared to the 4,000 cavalry and 1,000 infantry of the Persians. Less than 20% of the Greek mercenaries survived, and those that did were enslaved and sent to work in the mines of Greece.
The battle was won.
However, the battle had not proceeded entirely to plan. In fact, Alexander narrowly escaped death and was saved by his friend.
Rhoesaces managed to strike Alexander on his head and broke a piece of his helmet off. Additionally, he forced him to the ground and hit at his chestplate. Spithridates, seeing this, attempted to make a fatal blow against the King but “Clitus, son of Dropidas, anticipated his blow, and hitting him on the arm, cut it off, scimitar and all”.