Of 300, Ephraim Lytle, assistant professor of hellenistic history at the University of Toronto, says, Sparta? No. This is madness:
We know little of King Leonidas, so creating a fictitious backstory for him is understandable. Spartan children were, indeed, taken from their mothers and given a martial education called the agoge. They were indeed toughened by beatings and dispatched into the countryside, forced to walk shoeless in winter and sleep uncovered on the ground. But future kings were exempt.And had Leonidas undergone the agoge, he would have come of age not by slaying a wolf, but by murdering unarmed helots in a rite known as the Crypteia. These helots were the Greeks indigenous to Lakonia and Messenia, reduced to slavery by the tiny fraction of the population enjoying Spartan “freedom.” By living off estates worked by helots, the Spartans could afford to be professional soldiers, although really they had no choice: securing a brutal apartheid state is a full-time job, to which end the Ephors were required to ritually declare war on the helots.
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300‘s Persians are ahistorical monsters and freaks. Xerxes is eight feet tall, clad chiefly in body piercings and garishly made up, but not disfigured. No need – it is strongly implied Xerxes is homosexual which, in the moral universe of 300, qualifies him for special freakhood. This is ironic given that pederasty was an obligatory part of a Spartan’s education. This was a frequent target of Athenian comedy, wherein the verb “to Spartanize” meant “to bugger.” In 300, Greek pederasty is, naturally, Athenian.