This chapter examines the wartime population policy, the balanced distribution of population that became deliberated in the process of creating policies for “national land planning.” It analyzes the debates relating to population distribution policies as well as policy-oriented research activities mobilized for national land planning, the wartime government’s “sacred mission” to construct the new order in East Asia by establishing the Greater East Asia Co-prosperity Sphere. By focusing on the population technocrat Tachi Minoru, the chapter describes how Tachi’s research reflected the political agenda of the wartime government, which primarily viewed the population as an invaluable resource to be deployed for the nation at war. It details how the research carried out with this understanding came to create the knowledge about gendered and racialized demographic subjects that were categorized around the notion of economic production and biological reproduction. The chapter also analyzes the technocrat’s research to illustrate the fragile nature of demographic knowledge produced for policymaking and concludes that the role of policy-oriented scientific investigation in wartime statecraft was by no means as stable as has been claimed.