Research on territories which have long been subjected to nationalist violence has tended to focus on the most radical manifestations of these struggles and their electoral and institutional consequences. In certain configurations, the involvement of nationalist entrepreneurs in socio-economic initiatives, environmental causes or women's mobilisations reveals a broadening of activism to a larger political scope. This broadening can contribute to diluting or, conversely, reinforcing purely nationalist demands while creating new opportunities for alliances with non-nationalist mobilisations. The French Basque region illustrates such a discussion. Basque nationalist politics has not only taken the form of a political movement but has also constituted a culture of citizen opposition in which the nationalist demand is as much an end as support for other struggles, notably socio-economic ones. The article adopts a socio-historical approach by going back to the main arenas in which Basque nationalism was formed and the struggles that have shaped it. Once having defined the concept of the culture of civic opposition, the article analyses three historical sequences from the 1970s until the 2020s.