This chapter presents the 1918–20 ‘moment’ in the British Empire between the First World War’s armistices of 1918 and the peace treaties of 1919 and 1920. That moment, we argue, was a challenging and transformative time for the Empire. While British authorities successfully answered some of the post-war tests it faced, such as demobilisation, repatriation and fighting the widespread effects of the Spanish flu, the racial, social, political and economic hallmarks of its imperialism set the scene for a wide range of expressions of loyalties and disloyalties, and anticolonial movements alongside demands for more development and more opportunities immediately after the war as explored in the book’s chapters. The chapter defines the 1918–20 ‘mom...