Friday, August 21, 2015

Open and closed state systems: the geography of regional unification

Recurring periods of unification were a notable feature of the history of China; notably the Qin-Han (221BC-220), Sui-Tang (589-907), and Yuan-Ming-Qing (1271-1912) periods of unification. (The Northern Song [959-1126] arguably do not count as a full unification, since they never controlled the northern regions, which was under the control of the Liao dynasty [907-1125].) Indeed, of all the major civilisation centres, China was unified more frequently than any other.

Conversely, Europe was never unified and the Mediterranean basin was unified only once--under the Roman Empire. So, why was China repeatedly unified, while the Roman Empire was a one-off?

Unification propensities
The first thing to note, is that we are looking at different propensities to be unified. There were centuries-long periods of Chinese history when it was not united: nevertheless, compared to other civilisation centres, it showed a relatively high propensity for unification. Conversely, the Mediterranean basin had a low propensity to being unified (it was unified once) and Europe as a whole effectively no propensity to being unified (as it never was).

Size of largest and second largest empire.
Note also that propensity to unification is not the same as any more general propensity to large states or mega empires. The former is about the propensity for a specific region to be ruled by a single state, not mere state size or capacity. (Though, of course, state capacity matters in the sense that the region has to be within the possible ambit of control by a single state, given the level of organisational capacity achieved by states in a particular time period.)

Both historical demographer Peter Turchin (here) and historian T. Greer (here) have posted on the contrast between China and Europe. Both of the them reject what Greer calls the fractured land hypothesis, which Greer describes thus:
... they suggest that China's political unity and Europe's perpetual disunity are reflections of the unbroken terrain of the first and the disparate geography of the second. Two prominent examples can be found in Paul Kennedy's Rise and Fall of the Great Powers: Economic Powers and Military Change, 1500-2000 and Jared Diamond's Guns, Germs, and Steel: The Fate of Human Society.
Turchin and Greer both argue that the geography of China is more similar to Europe's than the hypothesis requires.

I completely agree with them, the fractured land hypothesis is not at all a satisfactory explanation of the different propensities to unification. Greer concludes his post with:
A close examination of the geography of East Asia suggests that there is no geographic feature capable of explaining the divergent paths of European powers like Germany, France, and the Netherlands that cannot be found in China. Chinese unity did not come because of its geography. It came in spite of it.
While completely agreeing with the unsatisfactory nature of the fractured land hypothesis, I completely disagree with Greer's wider conclusion. China's geography does explain why it had a relatively high propensity to unification--provided we look at in terms of the interaction between geography and state systems.

State systems: how bounded?
In using the concept of a state system, I am adopting the terminology and definition of historical sociologist Charles Tilly in his seminal Coercion, Capital and European States: AD 990-1992:
States form a system to the extent that they interact with each other regularly, and to the degree that their interaction affects the behaviour of each state (p.162).  
To explain varying propensities to unification, we have to examined how open or closed, how bounded, a particular state system is. A state system is completely open if it has no borders without effective states (or power projection by states). The contemporary global state system is completely open, it has no such geographical borders. But we have not always had a global state system: in fact, far from it.

A state system is completely closed if it is bounded on all sides by borders without effective states (or power projection by states). Apart from some early periods of state formation in various regions, this has essentially never been the case. A state system can be relatively closed, however. If, for example, all but one border is without effective states (or power projection by states).

The closed and controllable state systems of China
Which is precisely the situation that China was in for most of its history. Until the C19th, no state projected significant state power across its coasts. With the exception of the relatively brief Tibetan Empire (618-842)*, no state projected significant state power into China across a South-to-West-to-North arc from the Vietnam border to the steppes. For most of its history, the only open border for the projection of state power into China was the steppes border.

The interaction between the people of the plough (the Chinese) and the people of the bow (the pastoralist nomads) has been central to Chinese history. But it has been central to Chinese history precisely because, for the overwhelming majority of Chinese history, it has been the only open border across which external state power was projected into the farming lands of China. And that was most emphatically been a product of the geography of China. That its agrarian heartland is a series of river valleys bordered by coasts, jungles, mountains and deserts across which state power was not seriously projected from outside (with the above noted relatively brief Tibetan exception) and by the steppes, across which it was. 

Why does that matter for the propensity to be unified? Because the area that is so bounded was able to be controlled (given the transport and communication technology available) by a single state. So, in a period of disunity, if and when one state gained a military advantage over the others, the geography of China meant that the period it needed to sustain that military advantage to roll up the other states in the bounded state space was relatively short. Short enough to generate China's relatively high propensity to be unified. And, since there was effectively only one border across which rival state power could be projected, there were considerable economies of scale in military effort to be reaped once unification was achieved.

As we are looking at the interactive dynamics of state systems--that is, their movement through time--both military and administrative technology matter. In particular, what level of resource mobilisation states in the relevant state space have the organisational capacity to do, matters. It may take considerable time before one participant develops the organisational capacity to overwhelm the other states in the relevant state space. Hence centuries of disunity even in the case of China. Since we are looking at varying propensities, while geography remains essentially a fixed constraint, only explanation in terms of dynamics--specifically, state system dynamics, given that we are looking at the propensity for the state system to evolve into a single state--has any chance of explaining the pattern.

The Roman exception
If we look at propensity to unification in terms of characteristics (and the dynamic possibilities and patterns therefrom) of state systems, we can see why Europe had effectively no propensity to unification. Once state formation had spread beyond the Mediterranean littoral, it was never a closed state system in the above sense. There were too many borders across which state power could be (and was) projected into too large an area for establishing and maintaining unified control. Which meant too many directions from which unity could be blocked and (especially) military dominance blocked (as a series of would-be hegemons found).

The centuries earlier Mediterranean world that the Roman Republic confronted was quite different. There were no states beyond the Mediterranean littoral, except in the East. The forests of Europe, the deserts of the Sahara, were either empty of states or too much of a barrier for effective projection of state power. Only eastwards--in particular, the Iranian plateau--were there state(s) able to project state power into the Mediterranean littoral. Which was not enough to block Mediterranean littoral unity if one state had enough of a military advantage for long enough. 

The Mediterranean littoral was a large area, even given the utility of the Mediterranean itself for transport and communication. So, a state had to sustain a significant military advantage for a significant period of time to roll up all the other states and unify the Mediterranean littoral. But, if a state did, then the only border confronting significant state power was with the Iranian plateau. A geographical pattern which could generate significant economies of scale in military effort, if and when unification was achieved.

Which it was, because the Roman Republic did sustain such a military advantage for a long period of time, winning every external war for about three centuries. Long enough, indeed, to roll up every other Mediterranean littoral state and unify the entire Mediterranean littoral under one state.

Success that blocked replication
But the very success of Rome ensured that such a unification was a one-off, as the example of Rome spread the techniques of state formation beyond the Mediterranean littoral, which never again became a closed state system.  The Umayyad Caliphate and the Ottoman Empire made notable attempts at unifying the Mediterranean littoral, but it was precisely the Sahara-flanked region of the Mediterranean littoral--not that bordering the now too-deep European state system--which they united with the Middle East. Though neither controlled the entire African coast of the Mediterranean for as long as the Romans did.

So, I agree, the fractured land hypothesis does not explain the relatively high propensity for unification of China and the effectively zero propensity for unification of Europe; or why the Roman Empire was a one-off. But the interaction between geography and its effect on the dynamics of state systems does very definitely explain those patterns.

Geography matters in history; particularly before the Growth Revolution (to use T. Greer's nice phrase) from the 1820s onwards: for geography provided powerful, continuing constraints on human affairs. Only with steamship and railroads, from the 1820s onwards, (along with the development of telegraph systems from the late 1830s onwards) did humans develop any significant technological capacity to overcome the constraints of geography. It is not surprising that a recent study found that, prior to said Growth Revolution, geography appears to have dominated institutions in explaining the average long-run incomes of regions.

China was a relatively closed state system, with blocking boundaries, so had a high propensity to unification. The Mediterranean basin stopped being a relatively closed state system, so never repeated the Roman unification. While, once there was a European state system, it was never sufficiently bounded to be unified. All the results of the interaction of state system dynamics with geography.

[Cross-posted at Skepticlawyer.]

* The period of the Tibetan Empire coincided with the Sui-Tang unification, so China was already unified.


  1. I'd put more emphasis on the central plains, which are huge and fairly easy to conquer. Once somebody did unify the central plains, steamrolling everyone else was just a matter of time, especially after the Sui showed that the south is easily conquered by attacking through Sichuan.

    In Europe is much harder to conquer a large area to serve as base for further conquests. France is the closest thing, and it also was the strongest state by far, just not enough to steamroll everyone on 4 fronts.

    1. The central plains may have been the key target, but it was still the bounded nature of the Chinese state systems (a new one after each period of unification) which made unification repeatedly possible.

      Louis XIV experienced the resistance ability of the European state system--especially as England and the Netherlands had access to extra-European resources. Napoleon had the sustained military advantage, but it took too long (so other folk eventually caught up) and he could never get across the Channel while the Russians always had another 100km to retreat into.

      By the C20th, the European state system was now global: and again, neither the Hohenzollerns nor Hitler could get across the Channel: the former knocked out Russia but not France, the latter France but not Russia. The state system was too state-territory deep to be unified. Especially given the extra-European resources of the British and, well, the US.

  2. Thank you for this thoughtful response.

    I don't quite think the argument works, however. In particular, the 'bounded' concept only seems to work as a post-hoc explanation for developments. You essentially ask "why did China stay united and Europe not do so", but the relevant question is surely "how did China become united?" If you a ruler of Chu or Qi, the state system that surrounds you surely doesn't seem bounded. You would be surrounded by multiple aggressive states--the territory of what would become China was very, very state-territory deep. More state-territory deep than anywhere else in the world at the time. Lack of strong state polities on the periphery of Chinese civilization explains why it did not fall apart to external invasion; it does not explain why a state in the system was able to conquer the other strong polities in the system at all.

    A similar point could be made for China post Han, post Tang, and during the Southern Song.

    The broader question here is what caused the limits of political consolidation in any regime. Why could Paris unify all of today's "France" but never reach the Rhine? (re: spandrell's point, one notices the topography isn't much different from what we seen in North China). Why was the Iranian plateau repeatably unified by unitary states, but this rule was rarely extended past it? Why was Anatolia repeatably unified, but Hungary was not? And so on and so forth. From the point of the view of the decision makers of history, what is 'bounded' and is not clear. How can we explain things from the ground level?

    1. I am not trying to explain any particular unification, because that will be a contingent process about why particular state achieved a sustained military advantage.

      My point is that the bounded nature of the state system makes it unifiable in the right circumstances. The periods when China was "state deep" were not periods when it unified. The number of state players had to be reduced to a small enough number. But, the bounded nature of the system meant that it *could* be reduced to such a small number. Which was not true in Europe, or in the Mediterranean basin once state system had developed beyond the Mediterranean littoral itself.

    2. Also, I am not trying enunciate some general topographical theory about state size, but about the dynamics of state systems. Essentially, why does China alternate between having a state system and having system-abolishing unification, which other civilisation regions simply don't.

      Hungary is a difficult place to have a stable state since it has so many open borders. Anatolia, not so much. And France did reach the Rhine--under Charlemagne. As the European state system expanded, that became harder. Napoleon also managed it, due to achieving a significant and continuing military advantage, but not, as it turned out, enough of one for long enough. The state system was too deep: too many players over too large an area able to mobilise to many resources (some from outside Europe).

      The dynamics of state competition matter and interact with geography. The Iranian plateau was repeatedly unified because it is a geographically discrete plateau--something of a common ecological zone: the ability to expand beyond it depended on dynamics of state competition. The Achaemenids famously did, the Sassanians only for about 20 years.

    3. BTW, "why did China stay united and Europe not do so" is not the question I asked. The question I asked was: why does China have a tendency to unification which Europe never displays and the Mediterranean basin displays only once. The length of time of any particular Chinese unification is going to be a contingent question just as the length of time of any particular Chinese disunity is going to be a contingent question: the former on the dynamics of the Chinese state of the time, the latter on the dynamics of the Chinese state system of the time.

    4. Why exactly was the Europe of Napoleon 'unbounded' while the China of the Five Dynasties was not? From the perspective of Paris and Kaifeng the world would not have seemed too different. The state system of continental and Mediterranean Europe was strictly bounded. It extended to the Sahara in the South, stretched out to the Eurasian steppe in the west (as China's state system stretched to the Eurasian steppe to the east and north) and was bounded in its northeast by the Atlantic ocean. There was no meaningful 'deep state' presence in the Sahara, nor on the Eastern steppe. Scandinavia (and in early times perhaps England too) were peripheral players, relevant to the unity of European state system only as Korea and Japan were to the Sinic one. There was nothing inherent in either region's geography that made the conquest of one more difficult than the conquest of the other--except in hindsight. It seems very much that Napoleon's Europe is being described as 'unbounded' because he failed to conquer it, not because of any traits inherit in its state system.

      I am inclined to argue the opposite case: the 'deep' state capacities of the kingdoms of China made it easier, not more difficult, for the Chinese to 'unify' their state system.

      I haven't written up the post yet, but here is my view in brief: the most convincing and simplest explanation for Chinese unity is the continuity of imperial institutions throughout periods of disunity. When Rome fell, so too did the Roman bureaucracy. By the time the Omayyad, Carolingian, and Salian dynasties fell apart there was no European 'bureaucracy' to speak of. Rulers not only lacked the fiscal capacity to conquer--they lacked the means to incorporate their conquests into their own realms. In China things were different. The pattern is seen most clearly in the nomadic conquests. Barbarians from afar would come, declare themselves rulers over all of China, and then use the institutions of the state they just conquered to prosper. They were following an old pattern. When Song Taizu marched out from Kaifeng, he could be sure that every city he captured would strengthen him and provide more resources for his war machine. These states already had strong extractive capacities. He did not need to build new institutions to govern his conquests; he simply hijacked the institutions of his enemies.

      This also goes a long way towards explaining Rome's success. Rome conquered easiest where civilization was oldest. Spain's Mediterranean coast, dotted with small city states, long influenced by men of Carthage and Greece, was incorporated into empire centuries before the Spanish interior would call itself Roman. Gaul, dotted with oppida, was conquered to great acclaim; the Germans, who had neither polities nor cities to call their own, were left outside the empire. Egypt was brought into the empire in a twinkle. The "deeper" the states surrounding Rome, the better additions to empire they became.

    5. Sorry it took me so long to respond, and I will try and do so without writing a mini essay. First, by "state deep" I mean lots of states in a particular direction or directions. This is quite different from "deep state" as in deeply (and consistently) penetrated by state institutions.

      The question is not how it looked from an imperial capital, but how many direct state players there are in a particular state system. Napoleon had potential opponents in several directions at all times and across a much larger space than Chinese unifiers had to deal with.

      Yes, China suffered less disruption in culture and institutions, but that was because its geography meant it was not subject to the sort of disruptive invasions Europe was until quite late.

      Japan has no analogy in the European system since it was never a serious military player in China (even its incursion in Korea was blocked before it became so). Neither was Korea. China has no analogy to Britain, no equivalent to the Mediterranean, no real equivalent to Russia. It is simply much more closed geographically--which led to the cultural and institutional unity.

      Living in a globe where all inhabitable land belongs to a state, it is easy to forget that territory able to support state control was quite limited until quite recently. As the technologies of extraction, domination and control have expanded, the realm of the state has expanded.

      China, because the geographic barriers both blocked state control and projection but also enclosed a space within the range of control by a single state, was prone to unification. Once the technology of state rule had expanded into Europe, the Mediterranean was never such a space again and Europe simply never was such a space. Hence their relative propensities to unity.

  3. Why does that matter for the propensity to be unified? Because the area that is so bounded was able to be controlled (given the transport and communication technology available) by a single state. So, in a period of disunity, if and when one state gained a military advantage over the others, the geography of China meant that the period it needed to sustain that military advantage to roll up the other states in the bounded state space was relatively short. Short enough to generate China's relatively high propensity to be unified. And, since there was effectively only one border across which rival state power could be projected, there were considerable economies of scale in military effort to be reaped once unification was achieved.

    Or, to put it another way, China was mostly surrounded by Obstructive, Logistic and Cultural Boundaries, which meant that it was difficult for foreigners to intervene in the Chinese political system, and that once China was unified, it was (relatively) easy to defend. The Chinese very intelligently fortified and garrisoned these natural boundaries to make an inward creep of barbarians difficult; only when a great leader emerged among the barbarians was the Chinese system seriously threatened. Even then, the cultural influence of the Chinese was so powerful that the barbarians tended to be absorbed, neutralized and ultimately whatever of them was still alien rejected -- as happened to both the Mongols and the Manchus in the end.

  4. Indeed the Northern European plain is large too; but it was no where as rich as the Central Plains of China. Charlemagne conquered a big chunk of it; but holding it didn't produce enough resources for his war machine to push into Spain and the Balkans. While after the Sui, any decently managed northern state could very easily overrun the South.

    Not saying it's a larger factor than institutional, or even ethnic issues; but I do think there's a reason why the historical tradition puts so much emphasis in legitimate emperors "Lording over the Central Plains", besides mere tradition.

    1. Yes, it likely was the tipping point for dominance. But, then, the Ganges also provided a lot of resources, but we do not see the same pattern of unification in India, just a series of significant states and empires centred on the Ganges plain.

  5. What about the idea that Han Chinese are one big extended family? Europeans are many.

    1. Yes, but ethnic identity is not independent of state history -- read James C Scott's "The Art of Not Being Governed". Especially the imposition of a single writing form (which, one notes, supports various quite different dialects). Moreover, the ethnic congruence is itself not independent of the geography -- as it tended to block population flows into what is now the Chinese heartland.

    2. One also notes that ethnic diversity didn't stop the Romans.