Department of Ecology and Evolutionary Biology
University of Connecticut, Storrs
The Rise and Fall of Empires: why do large states tend to arise on the nomadic pastoralist/settled agriculturalist frontiers?
November 16, 2007
Lecture Hall 8, 4:00 PM
There is a striking macrohistorical pattern: largest territorial polities tend to arise at interfaces between settled and nomadic societies. An example of this pattern is the recurrent state formation in East Asia: China has been unified ~14 times throughout its history, and on all but one occasion the unification proceeded from North (and most frequently, Northwest) towards South. Simultaneously, a series of nomadic imperial confederations arose on the steppe side of the Inner Asian nomad/settled frontier. I will present a simple model providing a potential explanation for this empirical pattern. The basic idea of the model is that the anisotropy in military power between the mounted archers and the farmers puts farming communities under selective pressure to unite to better resist the predation from the steppe. In turn, the nomads are forced to unite to be able to overcome the defenses of the emerging agrarian states. The scale of polities on both sides of the steppe frontier increases in an autocatalytic fashion, until this runaway process is stopped by logistic and/or space limitations.
Biographical Sketch: Peter Turchin was born in Russia in 1957, educated at Moscow State University, New York University (B.A), and Duke University (Ph.D. in Zoology). After a postdoc at the University of Washington, he worked for Forest Service Research, then moved to the University of Connecticut, where he is Professor of Ecology and Evolutionary Biology. During the last decade his reseatch interests shifted from the study of population dynamics to the investigation of the dynamics of historical societies. Together with a group of like-minded scientists he is currently working within the nascent field of mathematical history. For more, see my Cliodynamics web page.