Secessionist movements involve sustained collective action by networks of actors claiming rights of withdrawal from formal state authority. Often, and especially in democratic contexts, these networks include both institutional and non-institutional actors. However, the relationship between the two has been regrettably overlooked despite literature has argued that political parties and social movement organizations are mutually dependent actors in shaping politics. Scotland constitutes an interesting case in this regard because while Scottish political elites called for an independence referendum in 2012, grassroots organizations appropriated the Yes campaign in the run-up to the referendum. This referendum campaign was characterized by a particularly high degree of eventfulness which is about the capability of producing new relations and resources that catalyze mobilization. Studies on eventful campaigns have observed that the latter impact on the very movements that carry them out. In the course of the referendum campaign, interactions among a plurality of actors were intensified and transformed. Secessionist networks expanded at great speed and debates were fueled by the interplay between different visions of independence. A qualitative study is conducted to explore the links between pro-independence parties and grassroots organizations both on the organizational and discursive level. By doing so, not only does this paper address the need to include non-institutional actors in the study of territorial contention but it also looks at them in interaction with institutional actors thus challenging the non-institutionalized vs. institutionalized divide.