Rokkan meets data: traditional cleavages, their preconditions, and a dynamic model of cleavage electoral structuring

The study of cleavages is undoubtedly one of the most debated in comparative politics. Lipset and Rokkan’s seminal study provided the foundations for the flourishing subsequent stream of research on the topic. The authors outlined the contextual characteristics that fostered or hindered the emergence and structuring of a given cleavage in a society and its political translation. Their claims are based on in-depth historical accounts and mainly rely on qualitative or even anecdotal evidence. This approach was entirely justifiable given the pioneering nature of their work and the scarcity of cross-country and cross-time comparable data. Over the last decades, concerns about data availability have been largely overcome as the development of large cross-national and longitudinal datasets has become an increasingly common practice in comparative research. Moreover, comparative historical analysis has started to regularly combine in-depth historical accounts with large-N quantitative data. Based on such premise, this paper aims to translate Lipset and Rokkan’s conditions for the emergence and structuring of the four traditional cleavages into empirically testable propositions. To do so, the paper devises and develops a dynamic model for studying the electoral development of cleavages. Many works on the topic assumed certain dynamicity in the evolution of cleavages, but such a process has not received relevant empirical attention. In other words, there has been no relevant study on the conceptualization and operationalization of a dynamic model studying cleavages. The proposed model builds on some key aggregate electoral properties of cleavage structuring, such as the electoral strength of cleavage bloc parties and the level of electoral mobility across the cleavage line. Thanks to this operationalization, the model is able to return, for each election in each country, the stage of electoral development of a cleavage. In other words, the model distinguishes contexts of cleavage absence, marginality, mobilization maturity, and crisis. The paper tests how Lipset and Rokkan’s propositions related to the emergence and structuring of the four cleavages translate into the different stages of cleavages’ electoral structuring. This framework is applied to 18 Western European countries since the very beginning of the electoral competition, namely, since the first time one of the four cleavages had been politicized. Overall, the paper covers almost 370 parliamentary elections from the late 19th century to the publication year of Lipset and Rokkan’s book (1967). The paper discusses the implications of the empirical findings not only for the evolution of traditional cleavages and their ability to shape party competition but also for the emergence and politicization of new conflicts.