This Companion brings together 32 new essays by leading historians to provide a reassessment of British history in the early twentieth century. The contributors present lucid introductions to literature and debates on major aspects of the political, social, and economic history of Britain in a period that included the First World War, political upheaval and the foundation of the welfare state, economic hardship, women's suffrage, and dramatic social changes throughout British society.

The volume examines the international role of Britain as both a world power and a European power, discussing issues of relative economic decline and the effect of the First World War on Britain's economic status. The book also addresses controversial issues over the social impact of the First World War, especially on the position of women in work and society. There is also substantial coverage of changes in Wales, Scotland and Ireland as well as in England.