West Africa is also the source region for religions now practised across the Americas, and the mechanism was the Atlantic slave trade.
Between the sixteenth and nineteenth centuries several million people were shipped from this coast, and the ports through which they passed, Ouidah, Elmina, Bonny, Badagry and others, are documented in European commercial records in unusual detail. Robin Law's history of Ouidah traces how one such town's institutions, including its religious ones, were reshaped by the traffic over more than a century and a half.
What travelled was not a portable church. It was a body of ritual knowledge, held mostly in the memory of individuals who arrived without their communities, their shrines or their lineages, and who then reassembled something workable out of what several different peoples had brought. The concentration of particular origins in particular destinations explains the resulting map: Yoruba practice is heaviest in Cuba and Brazil, Fon and Ewe practice from the Bight of Benin in Haiti, Kongo practice in Cuba, Brazil and the southern United States.
The relationship since has run both ways. Practitioners in the Americas have travelled to West Africa to be initiated, West African priests have travelled to teach in Havana and Salvador, and the tradition's international literature is written in Spanish, Portuguese and English as well as in Yoruba. The atlas holds West Africa as the source region and the diaspora forms in a region of their own.