Are you certain that the civilizations you consider wealthy were not essentially 'equal poverty' with a tiny number of elites of top? From the article: "After t

Are you certain that the civilizations you consider wealthy were not essentially 'equal poverty' with a tiny number of elites of top? From the article: "After the fall of Rome, people actually got taller and healthier". A generic high standard of living for the common people does not necessarily raise conquering armies or monuments to capture the modern imagination. The contrast is mostly against more distributed societies that you might not recognize as 'famous civilizations' per se, perhaps were able to provide better for their inhabitants.