Family Language Policy (FLP), the explicit planning as well as the implicit, covert and unarticulated measures regarding management of languages in the family domain, has received increased scholarly attention in the last decade. Many past studies draw on Spolsky’s (2004) tripartite model of language policy, which views language policy as the culmination of language practices, language ideologies, and language management. Others have drawn on Curdt-Christiansen’s (2009) model of FLP, which considers socioeconomic, sociopolitical, sociocultural, and sociolinguistic factors and their influence on FLPs. Despite this, most past studies do not attempt to fully integrate all of these areas into their analyses. In this presentation, I propose adopting assemblage theory (Deleuze & Guattari, 1987) as a means for analysing and combining these complex, ongoing and intertwined processes, which ultimately combine to create a FLP. I draw on video-ethnographic and interview data from Swedish-British families in order to show how key moments from the data can be understood as the assemblage of diverse elements. In keeping with the theme of the conference, I pay particular attention to how recent global developments such as Brexit play a mediating role in these assemblages, and thus in the FLPs of Swedish-British families.