EU Politicisation in a Third Country Context: Evidence from Automated Text Analysis of Swiss Media

The politicisation of the European Union (EU) drives Euroscepticism in Switzerland, where frequent referenda and the mobilisation by a populist far-right party make European integration a recurring political issue. Yet we still lack systematic evidence on whether EU politicisation in Switzerland is constant over time or whether it peaks around major integration steps, polarising popular initiatives, or election. This study addresses this gap using newly developed automated text classification models to analyse a large corpus of Swiss media articles. The approach enables measurement of salience, polarisation, and actor expansion across time. The results show that politicisation is strongly concentrated around integration milestones and highly contentious popular initiatives but is largely decoupled from federal election cycles. Geopolitical crises such as the Russian invasion of Ukraine also increase the salience of EU-related issues in Swiss public discourse. Beyond the Swiss case, the measurement strategy provides a transferable approach for comparing politicisation dynamics across issues and contexts. The findings offer new insights into the timing, triggers, and intensity of politicisation processes and advance our understanding of how EU debates evolve in third-country contexts and how these dynamics relate to broader patterns of Euroscepticism.