Gyllenhaal, Arterton Join 'Prince of Persia', Because They're Both Clearly From That Region

After Alone in the Dark, BloodRayne, Dead or Alive, Doom, Double Dragon, Hitman, House of the Dead, Dungeon Siege, Super Mario Bros., Mortal Kombat, Resident Evil, Street Fighter, Tomb Raider, and Wing Commander, you'd think it would be getting pretty hard to find respectable actors willing to risk their reputation on a video game adaptation. Yet, for whatever reason, Jake Gyllenhaal and Bond girl up-and-comer Gemma Arterton have reportedly been persuaded to star in Jerry Bruckheimer's Prince of Persia. I suspect the cacophony of cash register bells that went off when they heard how much they'd get paid played a large part in the decision, but we can pretend it was that the director of Harry Potter and the Goblet of Fire and Love in the Time of Cholera (also, Mona Lisa Smile) is at the helm, giving Prince a slight edge over the usual Uwe Boll fare.
I haven't played the Prince of Persia games, so could someone tell me if there's a legitimate reason why blatant caucasians are playing the roles of Persian royalty? Is it like The Love Guru, where it's explained early on that he's actually a white American raised there, and thus not the new Charlie Chan, or are we just using Alec Guinness in Lawrence of Arabia as a standard now?
Jake Gyllenhaal crowned 'Prince of Persia' [THR]

