Even though Herodotus is often referred to as the father of history, I know many historians are skeptical about much of his narrative. One issue that seems to draw their incredulity is Herodotus’ statement of the size of Xerxes invasion force. Herodotus relates that Xerxes counted his troop strength by having 10,000 men pack themselves tightly into a circle. A circle was then drawn around them and successive groups of men were then herded into the circle until the entire army was counted. Herodotus reports the total at over one million. Historians say this would have been impossible.
Later, Herodotus recounts a conversation between Xerxes and Demerotus, the exiled Spartan king, about the fierceness of the resistance the Lacedaemonians would present. Xerxes exclaims that even if the Lacedaemonians fielded 5000 men, the Persians would still outnumber them 1,000 to 1. A little quick math returns the total this time of 5 million.
As the Persians marched through the countryside, Greek kings that had provided the token submission of earth and water to the great king were asked to feast the army for one night as the army passed through their country. Herodotus reports that the kings each had to expend a total of 400 talents of silver to provide enough food for the army and golden dinnerware for the king. He reported that each client king had to collect grain and livestock to feed this massive host. Now, if you knew the average cost of grain, goats, chickens, etc., you could probably devise still a third number based on a man’s average food consumption for a meal.