Chapter 11 looks at human immunodeficiency viruses other than HIV-1 group M. This includes the other three groups of HIV-1 (groups N, O and P) as well as HIV-2. Their geographic points of origin are identified and an attempt is made to understand their very different fates: from two persons infected (HIV-1 group P) to seventy-eight million (HIV-1 group M). It is concluded that chance and geography played a role (i.e. whether or not the viruses had access to the capital of the Belgian Congo), as well as biological factors (HIV-1 group M being more transmissible). Then HIV-2 is examined: its simian source, geographic distribution, and lower pathogenicity and transmissibility. Through a review of the colonial and post-colonial history of Guinea-Bissau, its epicentre, it becomes clear that iatrogenic transmission must have been the driving force in the emergence of HIV-2. The path of this retrovirus is followed all the way to Goa in Portuguese India, and historical factors support the view that this may have been the first successful exportation of a human immunodeficiency virus outside Africa.