How do we approach the subject of British grand strategy today? This article seeks a new approach to this question. It argues that there is a gap of grand strategic significance between actually-existing Britain and the Britain its political elites tend to imagine. The colonial and imperial histories that helped constitute and still shape the contemporary United Kingdom have fallen through this gap. One consequence is a grand strategic vision limited to a choice of partner in decline—Europe or the US. Overlooked are the power political potentialities of post-colonial generations situated in multiple sites at home and abroad. In search of this potential, we lay the conceptual basis for a strategic project in which the British ‘island subject’ is replaced by a globally networked community of fate: ‘Brown Britain’. This entails reimagining the referent object of British strategy through diaspora economies, diverse histories and pluralized systems of agency. What might such a post-colonial strategy entail for British policy? We offer initial thoughts and reflect on the often occluded social and political theoretic content of strategic thought.