Berlin is often described as the site of sexual innovation in both popular and scholarly accounts of the history of sexuality in the twentieth century. Particularly in the inter-war period, the metropolis became an iconic symbol of gender-bending nightlife, an organizational centre for myriad movements of sexual emancipation, and a nexus of scholarly efforts to catalogue and understand human sexual comportment and identity. This chapter argues, however, that while there was certainly an explosion of public, literary, and medical interest in sex, sexuality, and sexual identity in early twentieth-century Berlin, the terms ‘invention’ and ‘discovery’ can oversimplify what was actually a very complex and contentious historical process. Focusing on a few examples of the divisions within queer communities – particularly the conflicts between feminist, lesbian, and transgender activists and the arguments emanating from the masculinist branch of the gay rights movement – it tracks how discourses about the morality of prostitution, the social impact of same-sex love, and racialized biological knowledge shaped definitions of citizenship in ways that still resonate and are still debated. It is this debate, rather than some kind of definitive invention of sexual identity, that makes this period relevant for our present.

A variety of social and political tensions have historically shaped the interconnections between sexuality and public history, including the display of sexually explicit materials for the general public, concerns about censorship and the role of institutional funders, and debates about the role of mainstream institutions to document the history of communities long targeted by the guardians of official memory. Some aspects of sexuality, such as marriage, have long been part of public history, while others, such as sex work, have only rarely been mentioned. LGBTQ+ history has been particularly controversial, so this chapter focuses primarily on LGBTQ+ sexualities in public history, including organizations, archives, museums, publications, exhibitions, grassroots history projects, digital media, and other venues.

Histories of monism have generally ended with the First World War and placed it within the context of the technocratic fantasies of liberal supporters of antipolitical Kultur in late Wilhelmine Germany. This article argues instead that monism achieved its widest practical dispersal during the Weimar Republic in the socialist milieu. It follows the path of liberal intellectuals from opposition to war and monarchy into the socialist movements, where they took leading positions in local government, union educational institutions, and the expanding universe of socialist cultural associations. There they sought to revise Marxism to bring it in line with their theories of biological and sociological evolution. The article follows key four areas of the socialist workers’ culture movement and examines how monism shaped the theories and practices of sex reform, free body culture, festival culture and educational innovation. It thereby demonstrates for the first time the central role of secularist dissent and monist worldview in some of the iconic utopian projects of interwar socialism.