This work investigates the historical trajectory and political efficacy of the British peace movement from the mid-nineteenth century through the end of the Second World War. Martin Ceadel, a scholar of international relations and political history, utilizes an extensive array of archival records and primary source materials to analyze how these organizations sought to influence state policy. The book argues that these groups operated as 'semi-detached' entities, maintaining a distinct ideological identity while attempting to reshape the realist foundations of British foreign policy.

Experts recognize this work as a foundational text for understanding the evolution of organized pacifism in British political life. Scholars frequently cite the book for its rigorous archival methodology and its balanced assessment of the movement's successes and failures.