In this innovative account of the origins of the idea of the League of Nations, Sakiko Kaiga casts new light on the pro-League of Nations movement in Britain in the era of the First World War, revealing its unexpected consequences for the development of the first international organisation for peace. Combining international, social, intellectual history and international relations, she challenges two misunderstandings about the role of the movement: that their ideas about a league were utopian and that its peaceful ideal appealed to the war-weary public. Kaiga demonstrates how the original post-war plan consisted of both realistic and idealistic views of international relations, and shows how it evolved and changed in tandem with the war. She provides a comprehensive analysis of the unknown origins of the League of Nations and highlights the transformation of international society and of ideas about war prevention in the twentieth century to the present.

Winner, 2023 Scott Bills Memorial Prize in Peace History, Peace History Society

‘This book reveals the complex intellectual foundations of the league of nations movement in Britain, offering a novel and sustained comparison between British and US views, and how the call for new world organization ties into the wider social history of the First World War.’

Patricia Clavin - University of Oxford

'An exciting analysis of the British thinkers who were among the most important originators of the League of Nations, and how they failed to resolve an issue as acute today as in 1918: how to avoid war without using war. A remarkable first book.'

John Horne - Emeritus Professor of History, Trinity College Dublin

‘Sakiko Kaiga offers an excellent study of ‘liberal internationalism’ in Britain before and during the Great War. By examining not only publications by Britain’s internationalists but also private correspondence among them, the author sheds much fresh light on the limits as well as the promise of an internationalism that existed side by side with imperialism.’

Akira Iriye - Emeritus Professor of History, Harvard University

‘Sakiko Kaiga’s Britain and the Intellectual Origins of the League of Nations, 1914–1919 is an attempt … to highlight the ideational currents that fed into that consequential moment in the spring of 1919, … it adds new and welcome detail concerning the work of key individuals and organizations in that history.’

Andrew Ehrhardt Source: International Affairs

‘The narrative is based on detailed and careful archival research throughout … the exceptionally rich, archivally informed narrative … makes this volume essential reading for those interested in discovering more about a key component of the British intellectual roots of the League of Nations.’

Thomas Davies Source: Journal of British Studies