|
100k is more of a fair number. Remember this is back when you still had to rely on messengers and smoke signals for communication. Its not like you can make a call to one of your sub commanders to have him mobilize a certain way. With any more troops, it would be better off to send them at various strategic locations, such as forming a giant flank or a blockade.
Equipment, experience, and discipline were also greatly in Alexander's favor. By that stage of his conquest, those who have followed him so far eastward were all true warriors, not merely people trying to defend their city.
Effectiveness of the persian army under their king may also be a deciding factor. I am unsure how loyal his men are (even before battle) given his fate after the loss - this leads to major control issues.
Most importantly, Alexander, as a conqueror, has a lot more experience in warfare than most of his foes.
|