In mid-1940, Austrians, Germans, and Italians in Britain were labelled 'enemies' by the government and subject to mass internment. In an anti-alienist climate they were targets of particular popular hostility. Neutral Irish also attracted hostility and suspicion as Fifth Columnists and spies. But after mid-1940 the British government moved to an increasingly complex view of nationality with Churchill taking a close personal interest in the recruitment of enemy nationals and neutral Irish to the British forces. Those who served came to be regarded as loyal allies. They faced charges of treachery from their fellow-nationals, demonstrating the assumption-common to Britain as well as Germany, Ireland, and Italy-that patriotism should be singular and exclusive. There is some recent literature exploring mass internment and the histories of Germans, Irish, and Italians in Britain after 1940. The literature treats national groups separately, but offers an opportunity for comparative analysis. This article puts Germans, Irish, and Italians in the same frame, focusing on those who contributed to the British war effort as soldiers, war-workers, and propagandists and tracing common transnational themes in their histories. Transnational allegiances are neglected in literature on transnational history, but were common to many Germans, Irish, and Italians in wartime Britain. Falling outside national memories, their histories have been largely forgotten. Those who gave their lives are rarely commemorated.