Hi, you might want to check out this thread from our FAQ, where /u/snickeringshadow delivers an awesome response that dispels the idea of teleological advancement and puts the evolution of human societies into perspective; anatomically modern humans have existed for 200,000 years, and in that time, societies in Africa, Asia, Europe and the Americas independently invented things like agriculture, urban settlement and sophisticated political structures. In this perspective, Africans and Aboriginal people weren't really as 'far behind' as many people think of them today.

His/her point #6 is the most important thing to emphasize for these kinds of questions:

There's no force pushing technology to "advance" in linear progression: This is really hard for many modern Westerners to wrap their heads around. In our culture we tend to see technology as something that moves "forward" or "backward" from "primitive" to "advanced". In fact, this is a cultural value that we've placed on technology traceable back to the Enlightenment and the Industrial Revolution, and not an intrinsic property of technology itself. As I hope I've explained with the above caveats, technology is actually more of an adaptive process. People create technologies to respond to perceived social and environmental needs, and there's no "forward" or "backward" motion to it, unless a particular society decides that there is. That said, when you look at the course of human history there does appear to be a particular directionality to technological change. (Not many of us today are hunter-gatherers, for example.) But this is not due to some force pushing technology to advance, but is rather due to the fact that once people have designed social systems and infrastructure that depend on a particular technology, it's hard to abandon it. (For example, personal cars are causing problems today re: global warming, but nobody's going to stop driving because we've come to depend on cars and have designed our roads and cities to use them.)

Anyways, I recommend giving their whole post a read. It's very good stuff and does away with the perception of humans advancing technologically in a linear fashion, with outliers being 'behind' or something similar.

This question is problematic, and is going to need some clarification before it can be answered.

In what way do you consider this wide range of different peoples and cultures "behind" the rest of the world? Would you consider the Aztecs "behind"? What about the African empires, of which there were quite a few?

At what point of cultural development do you consider people "advanced"?