This book uses a biographical approach to explore the Labour Party's relationship with European integration, moving beyond simple 'pro' or 'anti' labels to showcase the complexity of views that have existed. Its positioning within the 'biographical turn' emphasizes the importance of formative experiences in shaping such viewpoints - held by both familiar figures and more underappreciated voices. Taking a broad view of Labour history, the book covers the roots of Labour’s diverse thinking on integration from the 1920s to the recent past. Its significant intervention in the fields of Labour Party history, European integration studies, and history through biography, helps provide essential historical context for understanding Labour's current European policies.