Maybe it’s because Herodotus is so aptly referred to as “history’s screenwriter,” but I was less impressed by Iggulden’s interpretation of the events in The Gates of Athens than I was with his interpretation of Xenophon’s adventures. Where the story he told of Xenophon’s exploits was very faithful to the history, The Gates of Athens seemed to include a lot more supposition on Iggulden’s part, mostly to add interpersonal drama. Yet he is telling a story about some of the most dramatic moments in recorded history, and I wonder if added drama is really necessary.
I don't actually know how much this post will help you in ridding your works of pesky anachronisms, but the title just seemed to clever to resist. If you're not already familiar, an anachronism is a literary, spatial or temporal (usually temporal) transplant. A detail, a phrase, an expression, a device, or really anything else could be an anachronism; most commonly these are stock expressions or devices of our own time that we accidentally put into our works. Nor are they unique to literature, as there are plenty of examples in movies and other media. For instance, perhaps a period movie might show cars from a later model year driving around in the background. Or my personal favorite, when an author or screenwriter has archers "fire" their arrows, an expression which could not predate the advent of firearms. This last one even made its way into The Lord of the Rings movies (notably during the battle at Helm's Deep).
The Histories themselves are split up into nine books, which more or less focus on the Greco-Persian conflicts of that time period, with numerous digressions to talk about the history of Egypt, Babylon, or other places that come up.