The collapse of the Soviet Union meant for millions liberation from a regime that created the Gulag archipelago, in which their relatives, their friends and untold numbers whom they never met were incarcerated and/ or murdered; for millions more it meant the possibility to associate and interact freely with people throughout the globe; for still millions more it meant a catastrophic disruption of working life, of social security and of status in a new society they could hardly understand; for millions again it meant a feeling of hope, of security, of future possibility, as a member of a ‘nation’ that would now have its own state. Hardly to be compared with these earth-shattering effects, it is none the less noteworthy that the Soviet collapse has drawn scores of social scientists back to the seminal work of Ernest Gellner, who gave us a framework for analysing how nationalism arises, when it is powerful and when it is weak.

The most important contribution of Gellner's work on nationalism has been its unrelenting insistence that the existence of a ‘nation’ is not a sufficient condition for the emergence of nationalism; rather nationalism is the result of the uneven diffusion of industrialisation. The theory is evocatively explicated in Gellner's ‘just-so’ story, related in Thought and Change, which has a robust plot. In it, there are two territories, A and B, which are parts of an overarching empire. Modernisation hits the world ‘in a devastating but untidy flood’, coming first through A, and only later to B.