There's a picture of King Leonidas on the USA Today cover, looking Spartan with things sticking out of his chest and still able to bellow a war cry.

At first I wasn't sure I wanted to see it--those Middle-Earth monsters don't quite fit into the history lesson. I read an article in an obsessive-compulsive sci-fi magazine about the moviemakers' intentions with this movie, and then it all made sense. It's told from the perspective of the lone survivor of that conflict, and naturally stories tend to snowball into giant mythic narratives. Apparently the Middle-earth monsters are just Persian warriors who shared the Spartan quality of superhuman strength. The narrator just perceived them as monstrous because they were the enemy.