This dissertation traces how male gayness, while conceived of primarily as a sexuality, has provoked a variety of gendered positions, identifications, allegiances, and conflicts through the 20th and 21st centuries. Overall, I find that the evolution of gay identity in the Western Hemisphere has been generated by a rotation of arguments staking a claim on gay men’s gender—that they are true or imitation men, that they are true or imitation women, that they betray both categories altogether, etc. Analyzing a series of cultural discourses and aesthetic lineages, I argue that our sense of gay maleness today is still dominated by the conceptual architecture of the inversion model of 19th-century sexology—one of the first medical and cultural models for describing congenital homosexuality, which explained gayness as a psychic, spiritual, or otherwise internal femininity in a male body. While one of the oft-told stories of gay cultural progress in the 20th century tells of the collapse of this model and the conceptual division of sexuality from gender and of gayness from transness, my analysis shows just how imbricated these fields and identifications remain in our contemporary. I employ a method of careful historicism and rigorous close reading of literature, activism, and film to track how the enfolding of gender and sexuality in cultural discourses by and about gay men. Because this dissertation highlights so many moments of polemical claims about what the gender of gay men “really” is, my approach is decidedly anti-polemical, aiming to place seemingly conflicting discourses into conversation with each other to see what arises from their frictional embrace. Doing so, this dissertation bridges conceptual gaps between gay studies and trans studies, between gay studies and feminist studies, and between gay studies and the representation of masculinity.