Focusing on the transnational connections between the metropole and the empire, my dissertation explores the cultural dimensions of British imperial defense policy in the late nineteenth and early twentieth centuries, with a particular emphasis on cooperation with the self-governing colonies of Canada, Australia, New Zealand, and South Africa. The existing scholarly literature on Anglo-Dominion relations presents the period 1868-1914 as a monolithic struggle between the proponents of imperial centralization and the powerful sentiments of colonial nationalism. In contrast, I argue that any critical examination of the evolution of the Commonwealth must be situated within the cultural and intellectual milieu of late Victorian ideas about race. I demonstrate that a pervasive sense of pan-British identity shaped the worldview of white colonials and resulted in an unprecedented level of imperial cooperation. Furthermore, I explore how the racial and cultural hegemony of imperial elites pushed non-white participation in the defense of the empire to the margins, reinforcing the popular literary construction of Rudyard Kipling's "Gunga Din" and other "loyal" subaltern stereotypes. My dissertation thus revises our understanding of the broader imperial relationship and provides a comprehensive and more nuanced context for the meaning of "British" identity within the empire.