Description of Darius’s Army at Arbela. Alexander therefore took the royal squadron of cavalry, and one squadron of the Companions, together with the Paeonian scouts, and marched with all speed; having ordered the rest of his army to follow at leisure. The Persian cavalry, seeing Alexander advancing quickly, began to flee with all their might. Though he pressed close upon them in pursuit, most of them escaped; but a few, whose horses were fatigued by the flight, were slain, others were taken prisoners, horses and all. From these they ascertained that Darius with a large force was 155not far off. For the Indians who were conterminous with the Bactrians, as also the Bactrians themselves and the Sogdianians had come to the aid of Darius, all being under the command of Bessus, the viceroy of the land of Bactria. They were accompanied by the Sacians, a Scythian tribe belonging to the Scythians who dwell in Asia.387 These were not subject to Bessus, but were in alliance with Darius. They were commanded by Mavaces, and were horse-bowmen. Barsa?ntes, the viceroy of Arachotia, led the Arachotians388 and the men who were called mountaineer Indians. Satibarzanes, the viceroy of Areia, led the Areians,389 as did Phrataphernes the Parthians, Hyrcanians, and Tapurians,390 all of whom were horsemen. Atropates commanded the Medes, with whom were arrayed the Cadusians, Albanians, and Sacesinians.391 The............