This book uses Christian reactions to the Spanish Civil War to analyse the role and importance of Christianity in interwar Britain. This conflict is used as a proxy through which to discuss the status of Christianity in Britain because the Nationalists claimed to be fighting a Holy War against communist-atheism. This representation meant that the conflict was of considerable interest to Christians in Britain. British Christians frequently used the war in Spain to discuss their broader concerns. Many leading Catholics and fascistic Protestants argued that the events in Spain were an exaggerated form of the communist threat to Britain; by contrast, many Protestants used the war to voice their wider criticisms of Catholicism. Catholics responded to these chastisements by reasserting that members of their faith were patriots who resisted communist internationalism and atheism. Christian responses to the war, therefore, increased pre-existing tension between Protestantism and Catholicism. Similarly, Catholicism’s already difficult relationship with Labour was adversely affected by these movements’ reactions to the conflict. Labour’s involvement with the Basque children operations showed that it wanted to maintain relatively harmonious relations with Catholicism, but these efforts were unsuccessful. Ultimately, this study uses British Christian reactions to the Spanish Civil War to indicate that Christianity was actually an important aspect of interwar British society.