The origins of International Relations (IR) as an academic discipline are often associated with research at British and US universities inspired by Wilsonian idealism in the aftermath of the First World War. However, this paper argues, there are more nuanced intellectual traditions that transcend the chronological, geographical and thematic boundaries of what has conventionally been understood as early IR scholarship. In particular, it shows how nationalism and internationalism were used as rhetorical devices to underpin debates beyond the Anglo‐American sphere and before 1919. The paper first reviews how the conventional narrative of inter‐war ‘idealism’ evolved and how recent revisionist historiography has challenged it. The second part shows how neglected strands of literature contribute to the revised picture and highlights the role of nationalism and internationalism in channelling the study of IR from around 1900 to the Second World War.