Voting and Talking Turkey in the EP: Patterns of Ideological Contestation in Roll-Call Votes and Parliamentary Debates (2009–2024)

How is the rise of the socio-cultural (GAL–TAN) dimension reflected in patterns of contestation within the European Parliament's external relations? This article addresses this question through a case study of the EP's relations with Turkey, and a comparative analysis of two main parliamentary arenas of contestation: roll-call votes (n=222) and plenary speeches (n=3,834), across three full EP terms (2009–2024). Drawing on a novel dataset, the results show that Turkey's heightened salience during EP8 (2014–2019) activated ideological contestation. While socio-cultural issues exhibit inverted-U patterns, Turkey's accession crystallizes GAL–TAN polarization, challenging the cohesion of centrist EPGs, whereas democracy and Cyprus-related issues remain less contested. Similarly, speech frequency in Turkey reflects the new socio-cultural divide. However, its effect is conditioned by nationality (notably among Cypriot MEPs) and by institutional constraints that privilege the left–right dimension. The findings contribute to discussions on transnational political contestation and EU–Turkey relations by revealing how national, ideological, and institutional factors intersect to shape political contestation in the EP's external relations.