What happened to the souls of the people who died b4 the Missionaries got to them?

The Moores, the Aboriginies, the American Indians, the Inca's, the Aztecs, the whole of the world b4 the missionaries set out had countless generations b4 them. Not one of them had any idea of the Christian "God". If "God" hadn't bothered to get in touch with them then, because of their faith in false idol's, surely they're all burning in a big fiery lake in Hell, as per the Bible's rules. If the Bible IS true, then this makes no sense. Can the Christians out there explain this to me? Where are the throw-away soul's of these "Heathens" now? And why are they where they are?