Vernacular knowledge is a realm of discourses and beliefs that challenge institutional authorities and official truths, defying regulation and eluding monovocal expressions of the status quo. Unlike monolithic ‘truths’, religious or secular, vernacular knowledge tends to be dynamic, fluid, ambivalent, controversial, appearing in multiple forms and open to alternatives. Ranging through culturally, religiously, geographically, politically, and socially varied contexts, Vernacular Knowledge examines heteroglot expressions of knowledge revealed in various genres: traditional tales and personal experience narratives, rumours and jokes, alternative histories and material culture, placelore and ritual. Transmitted through multiple communication strategies (face to face, social media, online forums, publications, etc.) vernacular knowledge is shared and shaped communally but individually articulated and actualised. Covering various realms of the supernatural, such as ghosts, saints, spirits, magic, energy lines, and divination, vernacular knowledge also underpins beliefs and assertions such as those expressed in conspiracy theories, challenges to politically and ideologically determined creeds, and other socially compelling ideas that undermine prevailing wisdom. Vernacular religion operates in creative tension not only in relation to institutional forms of religion but also to secularism, state sponsored atheism and scientific rationalism. Both vernacular knowledge and vernacular religion consistently (though often invisibly) challenge the homogeneity of dominant discourses and the hegemony of institutionalised authorities in myriad contexts. This volume is dedicated to Leonard Norman Primiano (1957–2021).