Can secessionism be a basis for affective or social polarisation? Despite much research on recent independence movements, their relationship to polarisation, a key mechanism theorised as increasing the risk of violent conflict, remains less understood. We argue that the issue of secession can be a basis of affective polarisation along both policy and ethnic group lines even in the case of non-violent disputes, and posit a number of expectations regarding such secessionist-based polarisation. We test our argument with the case of Catalonia, a substate territory that has experienced a deep secessionist crisis since 2017, using new data from a panel survey and embedded experiments fielded across two key time periods. We find that individuals’ secessionist preferences condition high levels of affective polarisation, with pro and anti-independence advocates having strong negative views and stereotypes of one another. In addition, there is spillover in terms of stereotypes of associated language groups. We also document a group of moderates that exhibit far less polarisation. Finally, we provide evidence on the persistence of these overall patterns. Our results contribute to understanding the underexplored polarisation dynamics of secessionist movements, particularly in contexts where high intensity violence (e.g. terrorism, civil war) has not occurred.The project is organised around three thematic areas: (i) how trust within and between social groups and towards governance institutions emerges and evolves in contexts of rising inequality; (ii) how trust in unequal societies shapes governance outcomes through two intervening factors - political behaviour and social mobilisation; and (iii) the pathways through which changes in such intervening factors may sometimes result in inclusive governance outcomes, but in the breakdown of governance at other times. Each of these areas will incorporate detailed theoretical and empirical analyses at the subnational level in four countries - Colombia, Mozambique, Pakistan and Spain - affected by rising inequalities and characterised by unstable or strained democratic institutions. The absence of systematic qualitative, quantitative and behavioural data has hindered progress in understanding the links between inequality, trust and governance in countries outside North America and Western Europe. The project seeks to compile a number of unexplored data sources and collect new data comparatively across these other countries in order to fulfil this critical gap. This data collection will involve: (i) comparative individual-level surveys to understand contemporaneous levels of trust, and attitudes towards formal and non-formal local governing institutions, (ii) behavioural experiments under different inequality and political contexts to better understand the formation of trust under different scenarios, (iii) indepth interviews with key political actors in government, members of social movements and citizen organisations to understand how inequalities affect perceptions of governance and strategies of political mobilisation, and (iv) detailed compilation of archival data that will allow us to better understand how inequalities and attitudes have evolved across time and how different historical junctures may shape the governance outcomes we observe today.

Data of the first wave were collected between 11-20 December 2017, and data of the second wave were collected between 19-30 September 2018. Data were collected via an online survey designed by the dataset creators and contributors. It was scripted and hosted by the survey firm Respondi (now Respondi&Bilendi) –following the dataset creators’ instructions. Potential participants were invited to take the survey because of their participation in an online panel with the Respondi.