to be accurate:
300 is based off of 300, the graphic novel by frank miller, who was inspired by 300 Spartans, the movie, which was based off the story of the Battle of Thermopylae, back around 480 b.c.
some estimations put the persian army over 2.5 million, other, just a couple thousand. either way, the spartans rocked.
this is probably the number 1 movie I'm looking forward to. I've watched the trailer so much.
(totally stokes me up for developing the Spartan class in Realms of Mythology game... ... you heard nothing.)
according to the producers, they will try to keep it to the graphic novel and not the actual battle as much (although they keep the flow intact). fine with me, tho, as long as they give me a great movie with lots of stylized violence and gore.