I found William McNeill?
's Plagues and Peoples
, despite being about twenty years old, fascinating for the novel perspective it gives on human history (though it bears certain similarities with GunsGermsAndSteel
, a recent book by Jared Diamond). While clearly focused on diseases, he also emphasizes the effect of population growth (or the lack thereof) on the politics of nations. This strand of his argument dovetails nicely with what I consider one of the fundamental bases of international politics: that economic power and, more indirectly, population ultimately determine the international influence of a nation. I was first introduced to this argument by Paul Kennedy's The Rise and Fall of the Great Powers
, and despite various pithy comments by many intellectuals regarding that book and the ideas it contained, I have yet to see a real argument against the principle. Viewed from this perspective, the impact of epidemic disease on political history, more than the destruction of armies or individual rulers, is its effect on population growth and thus economic power. In the pre-industrial era, technology changed slowly enough so that for any particular human lifetime, technology was essentially fixed. This meant that labor productivity was fixed (though in areas with fewer diseases, people were healthier, which may also have affected productivity), and thus economic growth required growth in the labor supply. McNeill?
uses this argument to argue that the patterns of global epidemics accounted for changes in the balance of power such as the fall of Rome, the permanently undeveloped state of Africa, and the rise of European power after 1500. He also attributes the expansion of civilization to disease: humans living in urban areas provided a breeding ground for person-to-person infection such as smallpox and measles. Because these diseases coevolved with their human carriers, urban dwellers had acquired and genetic resistances against these diseases which isolated, non-urban groups did not. When the two collided, the urban diseases killed off the uncivilized groups, allowing civilization to expand much more easily than it otherwise could have; in essence, civilized carried with them an inherent, powerful biological weapon. The most extreme example of this phenomenon was in the Americas, where civilizations had emerged but with an apparent lack of indigenous urban diseases; when Europeans arrived, smallpox, measles, and other European diseases killed huge numbers of people in the indigenous populations, and the shock of such a dramatic drop in population made them fairly easy to conquer. McNeill?
also brings up an interesting point about the moral effects of such plagues: both the Amerindians and the Spanish agreed that disease was divine punishment, and the immunity of the Spanish in the midst of the massive deaths may have convinced the native people that the Spanish had divine right to do as they wished. These two strands of argument are fairly solid, but McNeill?
also raises more speculative arguments (in my opinion) relating disease to the eclipse of paganism by Christianity and similar ideological changes. All in all, though, a worthwhile book, and a useful reminder of how history can be steered by trends far beyond human control.--CurtisVinson