This paper will look at the impact of sport in terms of changing perceptions of Irish national identity. Two recent works with which I have been involved (Holmes & Simpson 2021; Holmes & Simpson 2023) put forward the idea of the changing nature of Irish nationalism over the past fifty years or so. The analysis in these works was focused primarily on Ireland’s relationship with the European Union, and we developed the concept of ‘nationalism in internationalism’ to try to summarise Ireland’s adaptation to membership. This broad idea is already established in the political science literature on Ireland and the EU, for example in the work of Hayward and Tonra. However, the analysis of Kathryn Simpson and I goes beyond the usual political and economic focuses for Irish-EU relations (particularly in our 2023 book), and seeks to include a strong social dimension alongside the more traditional political and economic perspectives. Our analysis includes some passing references to the role of sport in the evolution of Irish nationalism. Once again, this is well-worn territory, well explored in several works (see for instance Cronin 1999; Rouse 2015; McElligott & Hassan 2018). However, these analyses have tended to focus most on the role of sport in shaping Irish national identity, and less on the internationalisation aspect. The intention of this paper is to bring in that internationalisation dimension and to evaluate how it has affected the perceptions of national identity in Irish sport.