In the run-up to the Second World War, the War Office agreed to organize territorial units that recruited specifically on the grounds of English Welsh dual identities. These formations, which comprised the 99th London Welsh Heavy Anti-Aircraft regiment and the 46th Liverpool Welsh Royal Tank Regiment, began recruiting in 1939 from English cities with significant Welsh populations. This article explores the mobilization and performance of English Welsh identities during the Second World War and reflects upon why, at a time of global conflict, some English men opted to enlist on the basis of Welsh antecedents. Relatively little attention has been paid to the plurality of British identity in wartime or to how the existence of what historian Thomas Hajkowski has called “hybrid ‘dual identities’” within the constituent countries of the United Kingdom informed the functioning of Britishness during the Second World War. Making use of previously unpublished and original life writing sources, this article illuminates the significance of dual identifications across two nations at once—in this case, Wales and England—within the multinational state of Britain at war. Overall, by examining the intersectionality between subjective wartime constructions of kin, home, and nation(s), it points to how a sense of dual identifications could feed into recruitment patterns and potentially bolster combat motivation and morale. By highlighting the interconnectedness between constituent nations of Britain, and the complexities of identity formation within Britishness, this article adds to the literature that complicates the notion of fixed singular national identities and underscores the importance of dual identifications within and across the borders of the constituent nations in advancing our understanding of twentieth century Britain.