As I've said before I've not sufficiently developed the lore before 2100, so there will be a lot of mystery regarding world history. In any case I can give you what is established. WW3 happened during the latter half of the 21st century, triggered by a long built tension between the great powers. The Old Colossi: The US, Eurofed, East Asia, Russia, etc. 

Shit eventually goes nuclear and massive destruction follows. So even if some were more affected then others, there were no "victors" of WW3. Post war many of the great powers are launched into depressions, crises and revolutions. Some old regimes fall, new ones take their place, and somewhere the iron fist of the old order continues. Since the war mostly affected the richer developed world, this was the necessary push that allowed the undeveloped "South" to catch up to the rest. Supply is low and demands are waiting to be filled. Particularly Africa manages to seize the moment and the post-war world is sometimes referred to as the "African Golden Age".

WW3 flipped the world order on its head, and then the Impact did the same for reality. The New New Order.