Viral emergences follow well-worn networks of power, finding paths of least resistance•and therefore opportunities for viral spread•among communities with long histories of inequality and exploitation. Because a virus is neither living nor dead, it is an existentially social entity. A strand of nucleic acid encased within a protein envelope, a virus inserts itself into the host’s cells’ nuclei, hijacking the cells’ genetic process of reproduction to replicate itself. Because viruses opportunistically travel along paths of least resistance within individuals’ bodies and between people in larger networks, they shine a bright light on inequalities in power, in health, and in self-determination, vulnerabilities that provide opportunities for viruses to infect, adapt, and amplify. Taking these themes of viral opportunity as they connect to the political, economic, and social history of central Africa, this paper discusses the historical emergence of HIV-1M in southeastern Cameroon between 1890-1950. My analysis of the biosocial contexts of the emergence of HIV/AIDS integrates oral histories of elders from southeastern Cameroon with German and French archival materials, integrating these distinct processes of knowledge-making about the convergent historical experiences in southeastern Cameroon into a powerful analytical perspective. This paper insists on analysis of convergent social, biological, and viral factors that must have been at work, simultaneously, to enable pandemic HIV/AIDS to emerge. Understanding viral emergences in African history provides conceptual handles for critical analysis of patterns in viral emergences today and in the inevitable future.