First, however, there was some tidying up to do and propaganda to take care of.
Exactly how many of the Great King’s soldiers had been killed it is impossible to say. Herodotus puts the total at 20,000, but this is probably just a guess. What is beyond question is that the casualties suffered by the Persian army were many, far more than those lost by the League army that had fought under King Leonidas of Sparta. But Xerxes wanted to present this battle as a great victory. He kept the bulk of his army and navy away from the battlefield while gangs of workmen dug large pits and hurriedly heaved the majority of the Persian bodies out of sight.
Only then was the rest of the vast army allowed to march through the Pass of Thermopylae. They will have seen the spiked head of Leonidas beside the roadside, the bodies of his men and the far fewer visible bodies of the dead Persians. Relays of boats brought over men from the fleet to see the battlefield. Xerxes wanted the battlefield presented as a stunning Persian triumph in which the impudent Greeks had been crushed by the overwhelming might of the Persian host. The battlefield certainly looked that way, but far too many people knew the truth.
from THE BATTLE OF THERMPYLAE by Rupert Matthews
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