The only place that collapsed into the Dark Ages after the Fall of Rome was western Europe. Indeed, at this point in history, the nation of Ghana would begin to develop, centered around the upper Niger, where merchants could buy raw gold, transship it across the Sahara, and sell it to interested parties at significant profit. China was halfway through a funk brought about by the fall of the Han Dynasty, India, Byzantium, and Parthia were puttering along nicely, and of course the Arabians were about to emerge in a blast of hell-hath-no-fury upon the world and then themselves (unlike the Germanics) become civilized.