The book argues that Atlantic slavery – as a practice of subjugation, a source of wealth and a focus of political struggle – was entangled with the production, circulation and reception of geographical knowledge. On the one hand, the debate over slavery was informed by, and involved the deployment of, geographical discourses, practices and representational forms, including maps, surveys and regional comparisons. In addition, more abstract debates were staged about how it was possible to obtain knowledge about different Atlantic places and who was best placed to do so. On the other hand, Atlantic slavery shaped geographical inquiries into Africa. Involvement in Atlantic slavery shaped European knowledge about Africa, while plans and proposals for alternatives to slavery, such as legitimate commerce, free labour settlements and the suppression of the slave trade, created a need for new knowledge to be obtained through exploration and the collation of existing geographical sources. Particular ways of understanding Atlantic commerce, including that associated with slavery, also found expression in how geographical knowledge of Africa was produced and made credible. No figure better encapsulates the entangled nature of African geographical knowledge and Atlantic slavery in the late eighteenth and early nineteenth century than geographer, plantation manager, Glasgow merchant and proslavery propagandist, James MacQueen (1778-1870). The book focuses on the West African facts and theories he promulgated, especially about the course and termination of the River Niger, and his proposals for increased British presence in Africa that were founded on these.