Good Riddance to the Roman Empire

Maybe Rome needed to disintegrate before the West could grow wealthy.

Escape From Rome: The Failure of Empire and the Road to Prosperity, by Walter Scheidel, Princeton University Press, 670 pages, $35

Walter Scheidel makes a dramatic claim in Escape From Rome: The collapse of the Roman Empire made the modern world possible. The release from imperial governance, he argues, had an outcome in Europe that was not replicated elsewhere. That in turn explains why Europe became the birthplace of modernity.

Scheidel, a Stanford-based historian, argues this thesis with an amazing erudition and a sweeping synthesis of scholarship. There is just one major weakness in his analysis, and it can be addressed without abandoning the main argument. Indeed, addressing it strengthens the already compelling case.

Escape From Rome belongs to what is by now a well-established genre of historiography: books that try to explain the nature and origins of the modern world. Works of this kind all have to account for the central feature that distinguishes modernity from previous human history—the enormous and unprecedented increase in wealth produced by sustained intensive economic growth. Since roughly the middle of the 18th century, ever larger numbers of human beings, over more and more of the planet, have escaped the constraints that had bound their ancestors since the advent of agriculture. Scheidel calls this "the Great Escape."

The challenge for every author in this genre is to explain why this process of liberation started when and where it did. Most recent accounts point to the ways Western Europe became strikingly different from other major civilizations in the later 17th and early 18th centuries—what the historian Kenneth Pomeranz calls "the Great Divergence." But Scheidel thinks the real divergence happened much earlier.

Scheidel's argument has three main elements. First, he attributes the sustained intensive growth of the Great Escape to innovation of all kinds. This, he says, was made possible—indeed, was encouraged—by a political order of polycentrism.

In Scheidel's usage, this means a system in which major densely populated geographical regions are divided into a large number of smaller and competing territorial states rather than being ruled or dominated by large and long-lived empires. Those states, in turn, are relatively decentralized, with many competing centers of power. This competition provides both space and incentive for experimentation and diversity, and it limits elites' ability to stop them. Large empires, by contrast, can provide stable government but have a strong impetus to smother innovation and variety. (This is the almost exact inverse of the argument put forward by another Stanford historian, Ian Morris, in his 2014 book War! What Is It Good For?)

Second, Scheidel argues that the Great Divergence and subsequent Great Escape first happened where they did because Europe was more polycentric and less prone to empire than the other densely populated parts of Eurasia, with the sole exception of Southeast Asia. China is at the opposite pole, having been ruled by empires for most of its history. The Middle East and South Asia occupy intermediate positions, but they have been sufficiently prone to empire to stop a robust and lasting polycentrism from appearing.

In a fascinating and arresting section, Scheidel argues that the proclivity to imperial governance is mainly determined by geography—above all by proximity to the steppes and deserts of Eurasia. Because of its internal geography and its physical location relative to the steppes, Europe in general and Western Europe in particular have been much less likely than other regions to develop a single dominant empire. Steppe and desert nomads living in proximity to settled civilizations want the products of those societies, through trade or, frequently, plunder. This leads them to organize into large confederations or "mirror empires" (a term Scheidel takes from the anthropologist Thomas Barfield), and these, combined with nomads' military effectiveness, makes them a serious threat to the settled civilizations. The response is to develop a significant fixed military capacity, which encourages the formation of large and long-lived empires.

The third part of Scheidel's argument tackles the most obvious problem with the second part: If Europe is less likely than other places to be united under imperial rule, how to explain Rome? Scheidel's answer is ingenious. He argues that the unification of all the lands around the Mediterranean, along with significant parts of Atlantic and Danubian Europe, was an inherently low-probability event. But the Roman Republic fortuitously hit upon a form of social, political, and military organization that, once established, proved almost impossible to stop before it had conquered all of those lands and reached its natural and social limits. Once established, it proved to have considerable staying power, but eventually it collapsed and, like Humpty Dumpty, could not be put back together again.

In China, the collapse of the Han Empire was followed after an interval by the reconstitution of an imperial state by first the Sui and then the Tang. But the collapse of Rome led to the emergence of a particular kind of polycentric system, which proved not only stable but expansive, spreading beyond the lands once controlled by Rome to other parts of Europe. And so, Scheidel concludes, the first Great Divergence between Europe and the rest of Eurasia happened in the sixth century. It made the second Great Divergence possible, leading eventually to the Great Escape.

The first main element of Scheidel's argument is almost certainly correct, and it is in line with what a range of authors have posited. The second part is one that I have been skeptical about in the past, but Scheidel makes a persuasive case. He does an especially impressive job of deploying two techniques that more historians should use. One is geopolitics—the connections between geography, the natural environment, and the social orders that people create. The other is counterfactuals through which he tries to determine whether the course that history took was contingent or determined.

The third part of his argument is more problematic. Scheidel argues convincingly that, once the Western Roman Empire collapsed, the chances of its being revived were vanishingly low. But he is much too dismissive of the chances that either Habsburg Spain or Bourbon France could have emerged as a hegemonic power (though he's right that neither could have unified Europe the way Moscow did the Russian realms). A hegemonic power would have had the same stultifying effect as an empire, particularly if combined with a restored Catholic monopoly.

That did not happen for two reasons. The first was Habsburg Spain's failure to defeat the Dutch, something that I'd argue was highly contingent. The second and more structural reason involves the military revolution of 1450–1650, in which warfare was transformed by the introduction of gunpowder. The pre-existing division of Europe meant that several powers simultaneously adopted the new military techniques, so no one gained a sufficiently decisive head start. This created a dynamic in which blocking alliances arose to check any potential hegemon.

The bigger problem with the third part of the argument is this: If polycentrism is the key to innovation, why did it take so long to result in the second Great Divergence and the Great Escape?

Scheidel writes as though there is a single continuous process running from the ninth century to the 18th. That is not plausible. The solution, which strengthens his basic model, is to argue that political polycentrism per se is not enough. One needs a certain kind of polycentrism, one where states have stable frontiers and stable systems of government. These systems must be powerful enough to check local predators and social resistance to innovation but not so powerful that they can smother the innovators. And they must be embedded in a stable system of interstate relations.

This never appeared in Southeast Asia (which is otherwise a puzzle) or during the episodes of fragmentation in the Middle East and South Asia. It also did not exist fully in medieval Europe. It did appear in Europe after the military revolution of 1450–1650 and was consolidated by the Treaty of Westphalia, which established an institutional order that regulated the relations between the competing states without a higher authority (such as the medieval papacy). You can still argue that this was the high-probability outcome of the way Rome collapsed, because that collapse gave rise to a system in which the military revolution could have the results that it did.

The perils of empire are visible everywhere today, and so are the drawbacks of a web of constraints that check experimentation and impose conformity. Ian Morris concluded his praise of empire in human history by arguing for an American world imperium. This book is the antidote to that dangerous vision. We owe our current good fortune, Scheidel reminds us, to the collapse of one of the world's greatest empires and the failure of every attempt since to revive it.