It is a commonplace of contemporary political science that the world is largely divided up among a set of states with equivalent de jure sovereignty, but at the same time some states, the Great Powers, are more equal than others in terms of their capacities to impose rules and norms of behavior—the projection of their sovereign power—including which de facto states get to be blessed as de jure in the first place. The paradox of unequal effective sovereignty is sidestepped by seeing the former status—you are one of us, at least juridically—as dependent on the recognition accorded by the latter—the Great Powers. This matters because without it, the presumption that there is a system of states in which each state can be modeled as the same as all others, rather than as simply Great Powers versus supplicant and dependent pawns, completely breaks down. Investigating the political dynamics of recognition as new states enter “the system” is important, therefore, in providing empirical evidence for the presumption that there can be a system at all.

Power Politics and State Formation in the Twentieth Century is the first book I have seen that systematically tackles this central conundrum of international relations theory as it is currently formulated. I cannot say that it answers it to my complete satisfaction. That would be difficult anyway because I think the notion of a naturalized state system is inherently problematic. But this book does raise a host of interesting questions and is based on an honest and sophisticated attempt at examining the role of external recognition versus so-called domestic and other international factors in achieving state independence using a mix of methods: a large-n quantitative study of 259 secessionist movements from 1931 to 2002 and historic-event data for two case studies, based on an analysis of secessionist efforts beginning in the 1990s in the former Yugoslavia and Soviet Union, respectively.

The take-off point for the overall study seems to be the observation that with the end of empires and decolonization, many commentators had expected state emergence to slow if not stop altogether. This was to miss the potential for state formation from a quite different direction: New states have emerged as a result of secession from existing states. So the focus of the book is not on all cases of state formation down the years from 1931 to 2002 but that subset, as the author says, whose birth “following independence demands far exceeds those born in other ways” (p. 7) such as unilateral decolonization or occupation and subsequent resurrection following a war. Of course, this does necessarily include a large number of cases that resulted from decolonization, in Africa in particular in the early 1960s, but that were associated with active nationalist movements. I have trouble seeing them as equivalent to the secession of Croatia from Yugoslavia or Kosovo from Serbia. Be that as it may, the book is based on a truly heroic effort to collect and model appropriate data in testing a set of hypotheses about the relative significance of external recognition, specifically that of the Great Powers (defined as the United States, United Kingdom, France, Russia, and China) in turning de facto states into de jure ones.

The seven chapters follow a clear and logical path. After an introductory chapter laying out the main claims and the organization of the book, the second surveys the existing literature about state emergence and finds that the role of internal control and legitimacy far outweighs consideration of external recognition (particularly by the Great Powers) in most accounts. The key assertion is that “[e]xternal legitimacy is the ultimate arbiter of state emergence” (p. 12).

A third chapter lays out the design and methods used in the subsequent three chapters and presents some detailed hypotheses about various potential domestic and system-level determinants of state emergence. Chapter 4 examines both the domestic hypotheses, such as whether federal systems or ethnic subunits are more likely to generate externally recognized secessionist states, and the preferred external recognition hypotheses including nuanced ones about the motivations of different Great Powers in extending recognition to de facto states. Using Cox proportional hazards regression models for the Great Powers as a group and individually, one major finding is that coordination between Great Powers in extending recognition has the largest overall impact on the likelihood of recognition. Different Great Powers also indicate different patterns of recognition over time because of the power of precedent for their own potential secessionist predicaments with, for example, the “probability of the United Kingdom’s and China’s recognition … significantly decreased in times of domestic vulnerability” (p. 76). Chapters 5 and 6 use sets of studies from the former Yugoslavia—Slovenia, Croatia, and Kosovo—and Soviet Union/Russia—Abkhazia and South Ossetia in Georgia, Nagorno-Karabakh in Azerbaijan, and Chechnya in Russia—to investigate the relative role of external recognition by Great Powers, with Slovenia and Croatia illustrating the importance of collective agreement and the others illustrating the vagaries of either no external recognition (Nagorno-Karabakh and Chechnya) or one-sided recognition (the United States, UK, and France with Kosovo and Russia with Abkhazia and South Ossetia).

A final chapter summarizes the main findings and strongly suggests that too much writing on civil war and secessionism misses or understates the role of external recognition, as does the practice of conflict prevention and resolution.

There are a number of real strengths to the book. One is that its global empiricism pushes away from the retelling of tales about supposedly prototypical European cases that still dominate so much discussion of the origins of statehood. Another is the thorough critical review of the established literature and its relative neglect of the role of external recognition. Finally, the combination of large-n quantitative analysis with the more in-depth historical narratives provided for the former Yugoslavia and Soviet Union/Russia provides a powerful way of steering the discussion between the poles of thin but useful pointers and thick but potentially idiographic detail. These are important contributions. The quality of the exposition in places, particularly of the tables in Chapters 5 and 6, does leave something to be desired. An entire column of data (on war deaths) is missing from Table 5.3, all of the tables in Chapter 5 have thoroughly jumbled footnotes, and in Table 6.1 an important percentage, that of Abkhazians in Abkhazia, is listed under Armenians.

I do see a number of theoretical problems with the book overall and in its detail. The entire role of the Great Powers as arbiters of the “system,” yet as presumably equal partners in it, remains outside the book’s framing of recognition by the Great Powers as crucial to other states’ emergence. Where did they come from and why them? The whole emphasis on juridical rights (de jure) against the empirical capacities of internal sovereignty (de facto) is also a very recent emphasis in international law, dating back at the earliest to the late nineteenth century and more specifically to the arguments of that great political scientist Woodrow Wilson at the end of the World War I and thus problematic in terms of the longue durée of statehood tout court (see, for example, Nina Caspersen, Unrecognized States: The Struggle for Sovereignty in the Modern International System, 2012). The Westphalian origin myth haunts this book throughout. Finally, is the struggle for recognition ever really over for any state? It is not just a “formation” problem. Arguably, even the Great Powers need to constantly invoke threats to their existence to mobilize internal and external allies alike. But recognition/legitimacy, as the act of secession itself attests to, is never simply inside or outside or finished once some Great Powers are on your side.