The ANR JCJC project The Castrati: Experiences of Otherness in Enlightenment Europe (CastrAlter) is led by a young researcher specializing in the history of gender, the body and sexuality. Over a period of 36 months, it brings together a post-doctoral fellow and researchers in human and social sciences (history, gender studies and musicology) from French and international universities. The project aims to historicize the notion of gender fluidity and to question the effects of unequal rhetoric and gender-related practices in early modern Europe by focusing on Italian castrati (16th-18th centuries). He thus questions the reception by the singers of artistic, legal, philosophical and scientific discourses which make them a repelling figure of the Enlightenment (in England and France more particularly, then from the 1760s within the current of the Illuminismo). Their castration does indeed produce a disturbance in gender norms, as it would cause both physical and moral effeminacy, in turn influencing their sexual orientation. Research on these singers, who are still scarce in history, has focused on normative sources that marginally evoke the views and experiences of castrati in the face of the processes of otherness which constrain them. By focusing on sources produced by castrati, confronted with other archival documents on their living and working environment, the CastrAlter project intends to study the variety of perceptions and social trajectories of singers. He postulates the existence of self-redefinition processes ranging from phenomena of over-virilization by castrati wanting to enter into social conformity to the development of models valuing markers of subordinate masculinity. Three lines of research have been defined from the documentation inventoried through preparatory programs. The time of socialization of the castrati in the Neapolitan conservatories will allow us to grasp the progressive shaping of the divo (celebrity of baroque music) as it emerges from childhood (axis 1). The time of stage practices, and in particular of international mobility in France and England, will be an opportunity to analyze strategies for adapting to criticism from audiences outside the peninsula (axis 2). Finally, the writing practices of the castrati will make it possible to question their own narratives concerning their gender identity, their relationship to the body, to sexuality or to filiation (axis 3). This socio-cultural history project also develops an interdisciplinary history / performing arts methodology, matured by the young researcher during previous collaborations with theater professionals. By integrating an artistic team, in particular made up of specialists in baroque opera (staging, choreography, singing and music), it is a question of considering scenic methodologies as possible levers for the development of historical hypotheses (relating to the bodywork, the notion of performance ...) on the experiences of castrati. In terms of impacts and spinoffs, the project aims to fill the lack of historicization of social groups challenging gender binarity in the early modern era and to shed light on the processes of contemporary historical filiation in the activist, artistic and scientific field around castrati. The valuation of the project will give rise to numerous publications (book, articles, journal files, Hypotheses notebook), to research instruments (database), a virtual exhibition, teachings within the master's degree in Gender Studies as well as a theatrical restitution (theatrical conference or documentary theater) which the artistic team of the project will take care of.