Xerxes Five Million Men

[hoplite14gr]

This statement by Herodotus I disagree with. Under the circumstances, I do not see how one could afford to have that many men stand by and watch the battles and eat food. In modern armies, even the supply guys are riflemen first, clerks second. It makes a lot of sense to me that the men employed in grain transport were full fighting soldiers, already counted by means mentioned previously. By making this statement H. is casually doubling the number of troops in a single stroke of the pen.

I must comment that if the Persian fleet had 1200 ships and half of them were triremes then that makes for around 120000 men Not all them would be combatants. Athenians alone could field 200 triremes so the whole of Persian Empire could certainly field more.
We know that in the Greek fleets the oarsmen were expected to fight. But in the Persian fleet only the Ionian vessels would possibly do that. Phoenicians and Carhidonians relied heavily on galley slaves and I do not know what is the case with the Egyptians. So yes there would be lots of poor wretches along with the fighting men.
If we accept 100000 men only then this might impress 7000 Greeks guarding Thermopylae but Herodotus say that even after Salamis the size of the Army left behind made the Greeks hesitant. If the Greeks could field 100000 troops hoplites and psiloi in Platea then how big must have been the army left with Mardonios to make them hesitant? And we talk about the army left behind not the initial army. So far the excavations in Greece say that at that time there were 10 cities in Peloponnese with enough population so that could field the same number of hoplites that Athens could (10000). Even if they sent only half that is a sizable Army for Greek standards. So how big must have been an army to make this people hesitant?