Escape from Rome: The Failure of Empire and the Road to Prosperity by Walter Scheidel (review)

Walter Scheidel's latest book is an oddity: an innovative and meticulously researched new work that proposes an old answer to an old question. Why did Europe rise to a position of global dominance in the modern era? In Scheidel's mind, "there is no bigger question for the historian" (p. xvii). His answer is polycentrism. Following a tradition that started in the Enlightenment era, Scheidel found the roots of European exceptionalism in the historical tendency of Europe to be divided externally into competing states and internally into rival interest groups, in contrast with the more monopolistic imperial structures that predominated elsewhere in Eurasia.

Scheidel organizes his argument around two "Great Divergences," redefining the term in the process. The "First" Great Divergence, he contends, began with the fall of the Roman Empire, the existence of which should not be taken for granted. Rather, Rome owed its origins and longevity to an unlikely constellation of causes; as Scheidel puts it, "Rome's manifold advantages . . . were so unusual that they were unlikely to occur again later—and in fact they never did" (p. 123). Other parts of Eurasia, in contrast, proved to be fertile ground for the repeated flowering of large, hegemonic empires. This was especially true of East Asia, where except for a few interregnum periods a single Chinese state would control an average of 80% of the landmass from 250 b.c.e. to the present.

The idea that fragmentation and subdivision laid the seeds for later European success is not a new one—the kernel of the idea, Scheidel notes, goes back all the way to Montesquieu. Nonetheless, Scheidel reworks this already-broken soil with exceptional skill. For Scheidel, several factors combined to render Europe unsuitable for large-scale empire. Scheidel notes that nearly half of Western Europe is located on peninsulas and another tenth consists of islands, far more than in East Asia and elsewhere. Europe's rivers were better suited to small-scale power generation and transportation than to large-scale harnessing through public works, as was the case in China and Mesopotamia, though Scheidel cautions against wholesale adoption of Karl Wittfogel's theory of hydraulic despotism. The geographic factor that mattered most, however, was Europe's distance from the central Eurasian steppe. States on the steppe margins had easy access to horses and consequently a decisive advantage against both internal opposition and external rivals. At the same time, these growing states were vulnerable to invasion by "shadow empires" of the steppe, confederations of nomadic pastoralists who sought to exploit their sedentary neighbors through trade, plunder, or "extraction of tributary payments" (p. 277). The threat of pastoralist invasion, in turn, further encouraged reactive state formation on the steppe margins. Such was the power of the "steppe effect," Scheidel contends, that virtually all large-scale imperial polities in history originated in or around the steppe. Rome's rise to power independently of the steppe effect was a historical anomaly, Scheidel notes, and after the First Great Divergence following Rome's fall the fractured successor-states of Europe were too remote from the Eurasian grassland for the steppe effect to exert any appreciable effect on European centralization.

This First Great Divergence would eventually bring us to the "Second Great Divergence," which is Scheidel's rebranding of the "Great Divergence" of Samuel Huntington and Kenneth Pomeranz: Europe's ascension to global economic, technological, and imperial dominance. For Scheidel, this second Great Divergence was crucially dependent on the first. Europe's stubborn post-Roman polycentrism fueled fierce inter-state competition which in turn served as a spur for technological development, a growing mercantile class, representative political institutions, protectionist trade policies, systems of public credit, and overseas expansion. What is more, drawing upon previous work by Joel Mokyr, Scheidel contends that Europe's decentralism facilitated intellectual development. In monopolistic China, the government had the...