Persian Invasion of 480 BC - articles

[Felix]

What technological advances made it possible for Napoleon to move 500,000 men, that Xerxes did not have access to?

You keep confusing global armies with field armies, Napoleon never moved a field army of 500.000, the top was around 130.000, thanks, as I already explained, to the supply lines system, that was unknown before the second half of the XVII century

As I recall, the 130,000 men were Davout's III Corps, oversized for this campaign. Other corps did march with the main force, but as mentioned just above this, they did so spread out up to a day's march apart.