As soon as Darius began to set his whole phalanx in motion, Alexander ordered Aretes to attack those who were riding completely round his right wing; and up to that time he was himself leading his men in column. But when the Persians had made a break in the front line of their army, in consequence of the cavalry sallying forth to assist those who were surrounding the right wing, Alexander wheeled round towards the gap, and forming a wedge as it were of the Companion cavalry and of the part of the phalanx which was posted here, he led them with a quick charge and loud battle-cry straight towards Darius himself.

Arrian, The Anabasis of Alexander

BIBLIOGRAPHY

1. Alexander the Great mosaic. Photographed by The Guardian. c. 100 BC.
2. Arrian. The Anabasis of Alexander; or, The History of the Wars and Conquests of Alexander the Great. Translated by Edward James Chinnock, commentary ed., Hodder & Stoughton, 1884.