Persian Invasion of 480 BC - articles

[Sean Manning]

Ok, here's an important question. Throughout history, has it always been logistical problems that have limited the size of an army? I'm not convinced that providing logistical support for a large army is as difficult as we are imagining.

Logistics have always limite the size of field armies of substantial states. The problem is worst for armies inland, because grain can only be hauled from a radius of a few dozen miles before your pack animals and bearers are eating most of their load carrying it to the troops. In an area with low-density agriculture and no decent roads an army can very quickly eat all the available supplies and be forced to move on or starve. (This may have been why Darius III advanced into Cilicia from western Syria before Issus). Water transport is 10 to 100 times cheaper, which is why great premodern cities are almost always on rivers, lakes, or the seacoast, and is why I think we cannot rule out Xerxes having invaded Greece with over 100,000 people (not all soldiers). However, the need to march out of camp in the morning through narrow gates, move through passes and over bridges, etc. also tends to limit the size of a practical field army. Engels' Alexander the Great and the Logistics of the Macedonian Army is the usual reference for these difficulties.