Japanese occupation of British Asia challenged British prestige at an unprecedented scale, but what the War challenged about Britishness went far beyond the myth of white supremacy. This chapter explains how the Second World War shattered the cosmopolitan, inclusive notions of Britishness that developed in pre-war Hong Kong. Even before the outbreak of war, systemic discrimination involved in the 1940 evacuation scheme made colonial subjects realize that Britishness was reduced to a ‘race’ at moments of crisis. The chapter also explored the varied wartime experience of Portuguese refugees in Macau, students and graduates of the University of Hong Kong, and members of the British Army Aid Group (B.A.A.G.). Increased interactions with the British state made some acutely aware of the racism they experienced under British colonialism, and eroded their identification with Britishness. The practicalities of war, then, highlighted the fragility of the rhetoric of imperial cosmopolitanism, and put the diverse forms of Britishness articulated in pre-war Hong Kong to a severe test.