The paper explores if classical social movement theories can be applied to explain the increasing presence of transnational activism in contemporary politics. I examine the empirical evidences of the Scottish and Welsh national movements, and find that although both movements have created certain transnational linkages, they remain issued-based and ephemeral. Transnational actions are taken mostly in reaction to the structural changes of political opportunities in domestic politics. Political opportunities arising from the Europeanization process have in their modest form influenced the beliefs and preferences of Scottish and Welsh actors, leading them to establish various degrees and types of collective actions beyond the British arena. The frames and mobilising structures used for transnational actions can still mostly find their roots back in domestic politics.
Keywords: Nationalist Movements, Transnational Activism, Europeanization, Political Opportunities, Frames, Mobilising Structures