A significant portion of the world’s population, especially in Asia, Africa, and Latin America, cannot conceive of atheism or a life without religion. In traditional societies, local beliefs permeate every aspect of life from birth to death, sanctifying all stages of socialization. However, in modern times, these beliefs have largely vanished in their pure form. World religions have not completely supplanted them, as this complex and contradictory process has taken many centuries. With the spread of world religions, many characteristics inherent in preindustrial societies’ beliefs have receded into the background. Ancient spirits and deities have become characters in folklore, children’s games, and songs, with traces visible in language and preserved customs. Adherents of world religions (and atheists as well) are often unaware of the connections between these religions and old traditional beliefs. World religions have incorporated many elements of more ancient religious faith. Practically everywhere, certain syncretic forms have developed (hence terms like “folk Orthodoxy”, “folk Islam”, etc.), which are an integral part of any culture. Without understanding this, it is impossible to adequately grasp the history of religions, political science, sociology, or even economics (one might recall, for example, the concept of “zakat” in Islam or tithing in Christianity). Therefore, alongside disciplines like theology and the spiritual practices of world religions, the study of the existence, interconnection, and mutual infl uence of religions is a key research area for anthropologists. This article highlights the importance of the anthropological study of this process, the close relationship between anthropology and religious studies, and the need to include this topic in the training and education of future anthropologists. The place and role of traditional beliefs in modern life and their future, and their interconnection with world religions, are demonstrated using the example of their existence among the peoples of Sub-Saharan Africa.