The key theme of this chapter is the first wave of institutionalisation of IR in the wake of the trauma to the European core. IR emerged tenuously in the core countries as a distinct academic discipline and policy science, with particular strengths in the US and Britain. Its main focus was on the immediate policy crisis confronting the core after the First World War: understanding its causes in order to prevent a second, giving particular attention to the role of armaments, diplomacy and the potential of the new League of Nations. Concern with the periphery stayed firmly in the background. A few institutions, university chairs and departments were dedicated to teaching and researching IR, and there was an annual academic International Studies Conference linked to the League of Nations that tried to define the scope and content of the discipline. There was also more thinking about ir in the periphery, though this remained largely marginal to Western IR.