Against all odds, nationalism has roared back in the American news. This was hardly a foregone conclusion. As a historic country of immigration, the United States traditionally has not been viewed as a single nation, but rather its polar opposite—a melting pot. Now we hear much talk of American (even Christian) nationalism, previously an oxymoron. To be sure, nationalism often came to the fore in Western Europe’s more ethnically homogeneous societies, and in the remnants of Eastern Europe’s multinational empires, as well as in former colonies in Africa and Asia. But today, the American invasion of Venezuela, Russia’s war in Ukraine, China’s threats against Taiwan, and Israel’s actions in Gaza and the West Bank are all justified in the name of nationalism.
Following Ernest Gellner, Nationalism and the Transformation of the State defines nationalism as a doctrine that requires congruence between the boundaries of states and nations. Whereas previous studies of nationalism largely concerned internal threats to the state by secessionist and irredentist movements, this pathbreaking book takes direct aim at its implications for all types of border change. Its senior author, Lars-Erik Cederman, a Swedish political scientist trained in Ann Arbor, has spent nearly three decades leading the program in international conflict research at Europe’s premier technical university, ETH-Zurich. This book includes 10 articles published in leading journals by recent members of his team.
The book unites two literatures—on nationalism and international relations—that have been mutually isolated and thus unable to satisfactorily account for border change. Each has its weaknesses. The nationalism literature fails to consider nationalism as an inherently territorial phenomenon, treats the state as a natural, unexplained entity, regards nations’ pre-modern past as irrelevant, and lacks sufficient empirical validation. For its part, the international relations literature also offers limited guidance. Whereas liberal analysts put their faith in the emergence of a peaceful and integrated world, realists criticize them for downplaying the power realities of world politics. Yet realists underestimate the power of ideology and nationalism’s subversive effects on state borders.
The book’s principal evidentiary base comes from a variety of maps of ethnic groups drawn by cartographers from across the European continent. Digitized map scans of the ethnic settlement areas combine all usable maps into one joint, time-bearing atlas of historical ethnic geography from the nineteenth century and, in some cases, earlier. These European maps are supplemented by world-spanning maps available since 1946.
Four types of ethnic border change are considered: irredentism, unification, ethnic secession, and ethnic collapse. One of the principal targets in the first part of the book is Charles Tilly, who famously proposed that war led to the territorial consolidation of states. This holds true only until the French Revolution; thereafter, powerful states began to shrink, principally due to nationalism. Nationalism introduced a new principle of political legitimacy—that political power derives from the people rather than the monarch. After the French Revolution, this shift from territorial to popular sovereignty put pressure on state borders that violates the requirement that state and national borders should coincide. While unification nationalism increased state size in the nineteenth century, thereafter its effects were dominated by secessionism, which shrinks states. Whereas nationalism exerts both integrating and disintegrating effects on states’ territories, the latter effect has prevailed since the twentieth century.
Ethnically fragmented states are more likely to experience secession, and thus to shrink, than more unified states. States whose dominant ethnic group is fragmented across state borders are more likely to attempt to incorporate their kin, and thus to expand, than states with unified kin. Ethnic secession is more frequent in ethnically fragmented states than in unified states. Unification is more likely to occur in states whose dominant ethnic group is fragmented across state borders. Irridentist border change is more likely to occur in states whose dominant ethnic group is more fragmented across state borders. In Eastern Europe, the situation was precisely the opposite: large empires were made up of many ethnic groups, some of which mobilized to become ethnic nations. An ethnic boundary between two locations increases the probability that they are or will become separated by an international border by 34% and 17%, respectively. Beyond Europe, ethnic boundaries explain border change since the 1960s in Asia, but not elsewhere.
To my mind, the most interesting part of the book concerns the influence of past golden ages on nationalist claims and conflict. Taking nationalist narratives seriously, it examines how the wish to restore past golden ages can be used to legitimize territorial claims and mobilize resources. Plausible golden ages are determined by combining ethnic settlement data with information on European state borders going back to 1100 AD. Nationalists typically legitimize their claims by mixing historical facts and fiction, sometimes dating back hundreds, or even thousands, of years. Such narratives make the case for restoring a past, idealized golden age. Rather than merely debunking nationalist narratives as myths and fabrications, they must be taken seriously. If millions of people share these views, aggressive nationalist projects cannot be written off as irrelevant, even if they misrepresent historical facts. Although they may offer a distorted view of a nation’s history, retrospective narratives have geopolitical consequences. Ethnic groups with a golden age polity experience a 320% increase in the risk of fatal interstate disputes.
Another study provides new evidence of the effect of railroad expansion on national integration from 1846 to 1945. Whereas it is conventionally assumed that industrialization contributed to national integration, the effects of rail expansion are far from straightforward. Separatism is more likely where railroads facilitate mobilization by improving internal connectivity of peripheral ethnic regions, and less likely where such regions are closer to the state’s capital. Railway networks can facilitate mobilization by increasing the connectivity of ethnic regions, but they can also decrease ethnic collective action by spurring state capacity.
The conclusion offers three policy implications. The first is that analysts need to be cognizant of the disruptive power of nationalism. States are far from the only actors in world politics. Ethnically defined nations are conceptually distinct structures that have played, and will continue to play, a central role in shaping geopolitical outcomes. The second is that nationalists are often obsessed with history, and that this obsession is much more than a curiosity. Any attempt to anticipate future nationalist moves and to respond to geopolitical instability requires an understanding of how and why nationalists are inclined to use and abuse history. The third deals with the best way of handling nationalist claims. Nationalism is an inherent part of the modern state system and representative democracy; it can persist or be contained. So far, little points to the possibility of transcending or even abolishing it entirely. Since giving in to nationalist demands may trigger a flood of political violence, ethnic power-sharing is an attractive alternative to contain nationalist grievances.
This is far from the whole story of nationalism’s effects on geopolitics. The book’s macroscopic data tell us nothing about the micro processes responsible for successful nationalist mobilization. If ethnic groups claiming to have had a golden age polity are 320% more likely to engage in interstate disputes than those lacking such a backstory, not every group succeeds in establishing restorative nationalism. Nationalism and the Transformation of the State is mute about the variable success of specific ethnic groups. That important task requires an analysis of the conditions governing nationalist mobilization.
