Addendum - Ancient army numbers

You'll note that in the preceding histories, I've mentioned few specifics about the numbers of soldiers engaged in a given battle or campaign.  That's because the topic remains a matter of long and intense debate where the only thing clear is that nothing is clear. We can say with relative certainty that there were about 6,400 deaths on the Persian side at Marathon because the Greeks counted them before burial. But what fraction of the  army is that? Modern estimates vary just as wildly as ancient ones.

For these reasons, I caution against speaking with certitude, even about the saw that Greeks tended to exaggerate the size of Persian armies.  You can say that such-and-such traditional number is wrong, but all that's left is educated guesses.  It's less exciting this way, but my preference in all cases is to just be honest about how little we know for sure.