Facebook has frequently been implicated in the 2016 ‘Brexit’ referendum result, and support for Leave has been linked to wider nativist and populist mobilisations online. However, close-up, qualitative sociological research has not been conducted into the relationship between Brexit and social media use. This is, in part, due to the computational turn in online research, which has led to a disproportionate focus on quantitative big data analysis. This article argues for the value of close-up, qualitative enquiry to facilitate situated understandings of the reality of social media use and what it means to individuals. It outlines one such methodology developed to investigate pro-Leave Facebook users, to demonstrate how challenges posed by such research can be overcome, and the opportunities such enquiry affords for studying the role of social media in contentious politics. Invaluable insights gained include the way Facebook provides an empowering tool for making claims to political knowledge in the context of growing transnational nativist and populist grievances.