Ireland’s military engagement in Spain and Hispano-Irish military cooperation in the twentieth and twenty first centuries

The chapter examines Irish–Spanish military connections during the twentieth century, with a particular emphasis on the Spanish Civil War and its legacy for later bilateral defence relations. It situates Irish military engagement in Spain within the longer tradition of Irish service in European armies, then traces how political, ideological, religious and diplomatic factors shaped Irish participation on both sides of the Spanish Civil War. The authors address the activities of Eoin O’Duffy’s Brigade and Irish volunteers in the International Brigades, as well as the impact of official Irish non‑intervention on military contacts between the two states. Its follows post‑civil‑war developments, outlining how Franco‑era diplomacy, neutrality in the Second World War, and later European integration framed limited but symbolically important Hispano‑Irish military cooperation into the late twentieth and early twenty‑first centuries.