the global population increased by less than 60% during the 500 years between 1000 and 1500 but then more than doubled (from about 460 million to nearly a billion) by 1800 – but remained overwhelmingly rural, with cities accounting for less than 5% of all humanity

It was also by way of the Mongolian trading network that the Black Death reached Sicily from the Black Sea in 1347, eventually killing up to a quarter of the European population. Yet the Pax Mongolica that extended over the vast part of Eurasia also ushered in a massive expansion of east-west trade that connected Western Europe and East Asia. Merch

Additional factors facilitating the spread of disease are the movements of armies and the expansion of international trade. The latter factor should be qualified by noting that international trade expands in the precrisis period (stagflation phase) and then gradually declines after the society has descended into anarchy. Thus, the rise of widesprea