Book excerpt: What are the origins of the hostile environment for immigrants in Britain? Chosen as a BBC History Magazine Book of the Year 2021 and shortlisted for the PEN Hessell-Tiltman Prize 2022 In the wedded stories of migration and the end of empire, Ian Sanjay Patel uncovers a forgotten history of post-war Britain. After the Second World War, what did it mean to be a citizen of the British empire and the post-war Commonwealth of Nations? Post-war migrants coming to Britain were soon renamed immigrants in laws that prevented their entry despite their British nationality. The experiences of migrants and the archival testimony of officials and politicians at home and abroad, retold here, define Britain’s role in the global age of decolonization.