Abstract: This study considers the flying of Palestinian flags by Celtic Football Club supporters in Scotland as an illustration of political activism in sport. Despite being over 4000 kilometres away and holding no ethnic, national or religious connections with any community involved in the Arab-Israeli conflict in the Middle-East, fans wave these flags to demonstrate backing for Palestinian people. With reference to an historical context of the ethno-religious origins of Celtic FC and its supporting fanbase being significantly composed of members of a multi-generational Irish-Catholic diasporic minority community in Scotland, through utilizing fan writings, self-representations, and the results of a small survey of supporters, this research provides for deeper understanding of the intermittent use of sport as a space for ‘taking sides’ in conflicts that have ethnic, national, religious, and political resonances. Critically, this insight also offers important reflections regarding narratives of antisemitism in football and beyond.