Source: Slavery, Civil War, and Salvation: African American Slaves and Christianity, 1830-1870 (LSU Press) 2010 A.D.
This source is confirmation for everything we already know. We already know many of the tribes of West Africa are monotheistic. We already know they practice core biblical beliefs that were transferred with those who were led captive into the different nations around the world through the Transatlantic Slave Trade. This source confirms that the reason why we were able to transition into Christianity at some point on a mass level is due to the fact we were already practicing an ancient, fundamental form of Judaism and then when we were delivered as prophesied by some Christian slaves the full, mass conversion took place.