This book examines how the British Broadcasting Corporation mobilized popular music to support the war effort on the home front and among the forces overseas. To an unprecedented degree, the wartime BBC programmed popular music and studied its audiences in order to build national unity, boost morale, and increase industrial production. The BBC also used popular music and jazz to promote the wartime values of virile masculinity, greater public participation for women, Anglo-American friendship, and pride in a common British culture. At the same time that it developed special programming for women factory workers and male soldiers, however, the BBC also came into uneasy contact with the threats of (ef)feminized sentimentality, Americanization, and new representations of nonwhite, racialized “Others.” It responded by regulating and even censoring popular music repertories and performers while listeners, the press, and Parliament energetically debated its decisions. Throughout the war, broadcast performances by singers like Vera Lynn and Anne Shelton; bandleaders including Geraldo, Victor Silvester, Harry Parry, and Glenn Miller; and theater organists like Sandy Macpherson helped reshape and reframe prewar understandings of gender, race, class, and nationality for the nation at war. This book argues that, rather than providing the soundtrack for a unified “People’s War,” popular music broadcasting at the BBC exposed the divergent ideologies, tastes, and perspectives of the nation.