Scholarship on the early modern practice of animal trials in Europe has grown substantially in the last few decades. After a critical literature review pointing at the shortcomings of positivist approaches and of the interpretation of the phenomenon as a purely religious practice, I present Foucauldian genealogy as a more rigorous framework for understanding the purpose this peculiar practice may have served. The benefits of adopting a Foucauldian perspective are twofold. First, it allows for a subtle functionalism that does not treat this tradition as a homogeneous block. Second, it gives an opportunity to introduce the animal body into Foucault's genealogy of power, which rather focuses on the human body and interhuman relationships.