When the Roman Empire fell – and scholars still debate how hard, and why – much was lost, including arts, literacy, public works, and the rule of law; but the most significant was the loss of commerce. The archeological record shows a drastic drop in quantity and quality of goods and materials in the 5th century, indicating the loss of artisans and skills. Without the umbrella of security, commerce faltered, forcing regions to become more self-reliant. Specialized skills fell aside as sustainment skills became critical. Artisans and artists were replaced by the jack-of-all-trades. It would remain thus until the relative...