The kingdom of Dahomey was documented by Europeans earlier and more heavily than most West African states, because it was a major participant in the Atlantic slave trade and European traders and officials were resident on the coast for two centuries.
That produces an early and detailed record with an obvious problem. The men who wrote it were engaged in the trade or dependent on it, and their accounts of the kingdom's religion sit inside arguments about its character that were, at bottom, arguments about commerce and later about conquest. French colonial rule from the 1890s added an administrative archive with its own aims.
Twentieth-century ethnography, from the 1930s onward, produced the first sustained attempt to describe the religion as a system on its own terms, and later work by Beninese scholars has continued it.
The tradition's own transmission is oral and initiatory. The Fa corpus is held in the memory of trained diviners, and the material of the convents is held by initiates under obligation. There is no scripture and no central authority that could produce one.
Since 1996 Vodun has had official status in Benin, with a national day and public ceremony, which has changed the visibility of the religion and the terms on which it is documented.
The atlas describes the structure and reproduces no convent material.