A lot of popular historical fictionthe type we see in games and movies and televisionis full of shit. Were so used to it being full of shit that, when Assassins Creed Odyssey opens during the Battle of Thermopylae, which, because its set in ancient Greece, is apparently obligatory, the player is mentally prepared for a very stupid video game.
Source: N4G PC Odyssey is Assassin's Creed at its best