The correct answer to this open question is the following.
In Africa, the belief in one god and in spirits resembling angels reflected the process of religious syncretism from the 1700s in that the African tribes intermingled their religious traditions, dances, chants, and beliefs, with the teachings of new Christian religions, to form a new way to live their spiritual system and express their beliefs.
The term syncretism applied to religion means that another religious belief system is mixed into an original spiritual system. The combination of both -ore more beliefs, in some cases- creates a new way to express religion in a tribe or community.