Arrian

“ For some of the men made gaps in the phalanx, and others locked their shields together. The waggons rolled over the shields without doing much injury, not a single man being killed under them. Then the Macedonians regained their courage, inasmuch as the waggons, which they had excessively dreaded, had inflicted no damage upon them. With a loud cry they assaulted the Thracians. Alexander ordered his archers to march from the right wing in front of the rest of the phalanx, because there the passage was easier, and to shoot at the Thracians where they advanced. ”

“ Then the archers shot at the Thracians who sallied forward, and repulsed them; and the phalanx, coming to close fighting, easily drove away from their position men who were light-armed and badly equipped barbarians. The consequence was, they no longer waited to receive Alexander marching against them from the left, but casting away their arms they fled down the mountain as each man best could. ”

“ At the age of 18 by his skill and courage he greatly assisted Philip in gaining the battle of Chaeronea. When Philip was murdered, Alexander ascended the throne, and after putting down rebellion at home, he advanced into Greece to secure the power which his father had acquired. ”