The migration of authority to regions has been an unmistakable trend across developed countries. It is also an important issue of competition, in which political parties play an important role shaping the salience of the debate surrounding decentralisation and driving the territorial reforms. However, the study of multi-level governance has too often been a ‘party-free’ area of inquiry. So, in this paper, we examine when and why state-wide parties address the issue of decentralization. In general terms, our study addresses the conditions under which institutional issues, often only weakly related to the predominant (left-right) ideological dimensions, become salient for political parties. The introduction of such new issues can have important consequences for party strategies, the relationship between issue-areas in party systems, and the choice of voters. In addition, the salience of decentralization may have an influence on when and how countries reorganise their territorial structures. In this paper, we consider factors at two levels: countries and parties. We expect that decentralization will be more salient in countries with greater regionally-based ethnic diversity, greater regional economic disparity, and more permissive electoral systems. We also expect that decentralization will be more salient among parties that face an electoral threat from regionalist parties. Moreover, parties will be more likely to address the topic of decentralization if the issue does not conflict with its other ideological views. Overall, our study provides an analysis of the structural, institutional and competitive factors that influence whether state-wide parties decide to make decentralization a salient issue. To test our hypotheses, we conduct a time-series cross-section analysis using data from the Comparative Manifesto Project from 1945 to 2010. Our findings have important implications for understanding issue-competition, the process of decentralization, and political conflicts over the jurisdictional allocation of authority in systems of multi-level governance.
