When Alexander learned of the concentration of the Persian forces, he advanced rapidly and encamped opposite the enemy, so that the Granicus flowed between the encampments. [2] The Persians, resting on high ground, made no move, intending to fall upon the foe as he crossed the river, for they supposed they could easily carry the day when the Macedonian phalanx was divided. [3] But Alexander at dawn boldly brought his army across the river and deployed in good order before they could stop him.1 In return, they posted their mass of horsemen all along the front of the Macedonians since they had decided to press the battle with these.2 [4] Memnon of Rhodes and the satrap Arsamenes held the left wing each with his own cavalry; Arsites was stationed next with the horsemen from Paphlagonia; then came Spithrobates satrap of Ionia at the head of the Hyrcanian cavalry. The right wing was held by a thousand Medes and two thousand horse with Rheomithres as well as Bactrians of like number.3 Other national contingents occupied the centre, numerous and picked for their valour. In all, the cavalry amounted to more than ten thousand. [5] The Persian foot soldiers were not fewer than one hundred thousand,4 but they were posted behind the line and did not advance since the cavalry was thought to be sufficient to crush the Macedonians.5 [6]
As the horse of each side joined battle spiritedly, the Thessalian cavalry posted on the left wing under the command of Parmenion gallantly met the attack of the troops posted opposite them; and Alexander, who had the finest of the riders on the right wing with him, personally led the attack upon the Persians and closing with them, began to inflict substantial losses upon them.