Norbert Elias's sociological analysis of ‘the civilizing process’ — the process by which modern European societies have been pacified over the last five centuries and emotional identification between the inhabitants of each society has increased — has much to contribute to historical–sociological approaches to International Relations. Elias analysed dominant attitudes towards cruelty and suffering in different phases of human history in his study of the civilizing process, his central purpose being to demonstrate the existence of a long-term trend to lower the ‘threshold of repugnance’ against public acts of violence within modern states. His observations about international relations were principally Hobbesian in nature, although Grotian and Kantian themes also permeated his writings. The latter are evident in his reflections on whether cosmopolitan emotions are stronger in the modern era than in earlier epochs. An empirical analysis of dominant global attitudes towards cruelty in world politics and an investigation of levels of emotional identification between different societies can extend Elias's study of the civilizing process. This form of inquiry can also contribute to the development of Martin Wight's pioneering essays on the sociology of states-systems and enlarge the English School's analysis of ‘civility’ and the ‘civilizing process’ in international relations. More broadly, new linkages between historical sociology and International Relations can be developed around an investigation of the dominant responses to cruelty and suffering — and levels of cosmopolitan identification — in different states-systems.