Imperial Island: An Alternative History of the British Empire - Hardcoverby Charlotte Lydia Riley (Author) This riveting new history tells the story of Britain's journey from imperial power to a nation divided one that alternately welcomes and excludes former imperial subjects and has been utterly transformed by them. In the turbulent years since the outbreak of World War II, Britain has gone from an imperial power whose dominion extended over a quarter of the world's population to an island nation divorced from Europe.