Many years ago in that world, in a deep sea of that world which is called the South Sea, a shipload of pirates were driven by storm on an island. And there they did as pirates would: killed the natives and took the native women for wives.Huh, what a euphemism! Anyway, they got drunk and fought etc, and six fled with their 'wives' and found the cave and the door to Narnia's world. So they'd be half Pacific Islander, and it's not a stretch that the pirates could hae been Spanish or some race other than English. The medieval Spanish feel in the film was a nice, slightly foreign touch, and the Wikipedia says that they deliberately used Italian, Spanish, and Portuguese actors.
Anyway I read on and book Aslan tells the Telmarines more about the island:
It is no bad place. The race of those pirates who first found it has died and it is without inhabitants. There are good wells of fresh water, fruitful soil, timber for building, fish in the lagoons, and the other people of that world have not yet discovered it.Aha, I said, it's the Lost island, and now we know who the Others are (and perhaps how Ben gets around in space and time).