The map shows the British Empire in 1900. Map of the British Empire in 1900. Areas marked in green are spheres of influence. Areas marked in red are lands lost by 1920. Areas in purple are colonies and dominions. Areas in orange are dominions. This map could help a writer draft a document-based essay about the British Empire because it demonstrates the spread of British imperialism all over the world. shows the locations of Great Britain’s dominions in South America. shows that the British Empire was limited to Africa and Asia. demonstrates that Great Britain’s influence was limited to Europe.