IIRC, Maximus was in charge of a single Legion, so that's 5,000ish men and his gaggle of gladiators. Xerxes' film army was said to be over one million. The Romans do have 600ish years of technological advancement over the Persians, but not sure that's going to be enough to overcome the 200-to-1 advantage the Persians have.
Probably comes down to terrain (like in 300) and if the Romans can make it so they're only attacking/defending from the front.
Do we know how big the entirety of the Roman army was at that time? Because if he was in charge of the entire Roman forces like Xerxes was for the Persians. Things could go different.
Well, if the odds are closer to 3 to 1, as opposed to 200 to 1, and given the couple of centuries in tech difference, if Maximus can find favourable terrain and do a competent job of commanding the Romans, I definitely see them as being able to beat back the Persians.
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Real life Romans versus the fiction demon creatures from 300?
I'm going with the monsters. Specially when they're 1,000,000 strong.
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