This study deals with transnational Shiism and the dynamics of relations between the Shiʿi religious establishment and the post-colonial state in Iraq. It sheds light on two aspects of transnational Shiism. First, the evolution and internal dynamics of religious authority, especially in terms of adapting its transnational domain to the Iraqi national context. The study argues that the relationship between Shiʿi religious establishment and the state was often characterized by tension, as the state sought to consolidate its power within its borders. Yet, after 2003, the nature of relations between the two has significantly changed, leading to new configurations of authority. Second, the increasing polarization between activist transnational Shiism, which is today led by the Iranian state, and Iraq-centric Shiism became a key factor in shaping power relations in post-2003 Iraq.