Scholarship on the International Relations of the Middle East (IRME) tends to uncritically embrace ‘moderate’ constructivism and mystify the origins of Arab nationalism. This is most clearly exemplified by Michael Barnett’s ‘dialogues model’, which has been critiqued for its Orientalist assumptions. As a consequence, Arab nationalism is mostly conceptualised as a parochial identity, which emanated from a diffused cultural normative structure and was in turn at state leaders’ disposal. Such an understanding suffers from the problem of ‘internalism concealed within ‘the international’’– approaching Arab nationalism through ambiguous, endogenous, and enclosed cultural contexts within a definite and universal world of sovereign states. In line with this issue, the extant literature on international relations of the Gulf has rarely undertaken a theoretical interrogation of Arab nationalism, examining how the origins and evolution of this ideology corresponds to a peculiar historical process of late-capitalist social and state formation in the context of the rentier economy. Instead, most discussions, wittingly or not, inherit a conceptually tangled view. It takes rentier-generated regime autonomy for granted, conceiving of Arab nationalism as an idea largely representing regimes’ political will on the one hand, and as a parochial norm diffusing across the Arab world on the other hand. In addressing the problem, this paper premises itself on the concept of uneven and combined development (UCD) and makes a historical sociological case for the social origins of Bahrain’s Arab nationalism under British colonialism. As recent research on the history of Arab nationalism suggests, prior to the opposition National Union Committee in the 1950s, al-Nahda movements in the 19th century formulated a prototype of Arab nationalism that influenced the later phases of Arab nationalist movements in Bahrain, contesting the fallout of British-led modernisation and gradually shaping the idea of national unity. The paper aims to build upon the recent historiography on Bahrain to explore an alternative theoretical understanding of the origins of Arab nationalism during the British colonial period, especially the first half of the twentieth century. It argues that Arab nationalism and its social origins should be better considered as a modern product of combined capitalist formation through colonialism. This ‘formation’ took off at the historical moment of oil commodification, as a social mechanism of combination. It then resulted in changing class relations and contradictions while creating vectors for the ideological evolution of Bahrain’s Arab nationalism in correspondence with social transformation.