The aim of our paper is to broaden understanding of the programmatic and emotional characteristics of the appeals of constitutionally illiberal political parties in Europe. First, we consider how constitutional illiberalism, which we define as opposition to liberal democratic institutions, connects with a range of other dimensions of (il)liberalism. Second, we investigate whether the appeals of such parties have a distinctive emotional content, for example by expressing anger or disgust. We study illiberal rhetoric through analysis of over 1m tweets posted by political parties in Austria, France, Greece, Hungary, Italy, Spain, Poland, and the UK between 2014 and 2023. To analyse the data, we develop and employ un/supervised machine learning classifiers considering democratic, institutional, economic, cultural and several other domains. We also measure emotional appeals in text via machine learning and dictionary approaches. Then, we study the communication dynamics between the public and political parties over time and domains to understand whether and how they influence each other in using such illiberal and emotive rhetoric.