At moments of historical shift, the debates about self and society more audibly acknowledge that the boundaries of subjectivity are porous and fragile – and gender, sex, and sexuality are integral parts of these boundaries. While non-cis/heteronormative individuals and relations appear throughout this book, Chapter 6, “Queer Identities and Activisms,” conveys their various iterations in modern and contemporary Japanese culture. Regarding such men: no law prohibited or regulated same-sex relations in Japan – with the exception of a brief period from 1872 to 1880. Yet, starting with the rise of new academic disciplines, around 1900 came the modern desire to know the “truth” about sexuality, to several ends: to legitimize knowledge about human sexuality within the academy, to bolster social reform, or, indeed, to use that knowledge for nation-building and nationalist and imperialist agendas. This chapter describes Japanese culture’s long-standing embrace of gender ambivalence, covering a range of nonheterosexual and gender-variant identities, practices, and communities that have come into being in Japan throughout the twentieth and early twenty-first centuries: namely, early “gay booms,” the more recent “new-half” individuals, and the current activism of LGBTQIA+ communities.