The objective of this research has been to further incorporate social dynamics, at the domestic level, to our understanding of international hegemonic orders from a social constructivist standpoint. As part of this theory building effort, the research is intended to contribute to the existing literature in IR theory by incorporating the concept of mass common sense in a theoretical framework of hegemonic depth (ranging from thick and thin hegemony to weak and strong contestation) that articulates three levels of analysis: international elites, national elites and domestic masses, based on Antonio Gramsci’s ideas on hegemony and mass common sense. In so doing, we can better understand and describe international orders and the conditions under which challenges to the international status quo by States in a hegemonic system can be expected. In the typological theory I have designed, four scenarios (types) describe different stages in international orders and foreign policy, and the explanatory mechanism lies in the different fits between the ideologies of international and national elites, and domestic mass common sense. As such, the framework accommodates but does not privilege either human agency or structural aspects. As a plausibility probe, a single case study has been created of Brazil during the Cold War years (1950 – 1980) in the period of the US-led liberal capitalist world order, to assess and further refine the theory. Qualitative discourse analysis has been applied to empirically map variations in how national identities, expressed in mass and elite texts, either reinforced or rejected the post-war liberal hegemonic order led by the US. A comparison has then been made of these ‘mapped identities’ with Brazil’s voting at the United Nations to judge whether Brazil challenged or adhered to that hegemonic order. The empirical study of the evolution of Brazilian national identities from a perspective of both mass and elite texts has been the second main contribution of this research. The results obtained from the empirical analysis have then been compared to the main literature on Brazilian foreign policy in order to assess their validity. Overall, the findings of the plausibility probe reinforce the hypothesis that domestic social dynamics are an essential component of 'thick hegemony', and a necessary condition for enabling major changes in international hegemonic orders.