This thesis gives an account of Augustine’s understanding of demons, a full-length study of which has yet to be published. I argue that the scriptural assertion that pagan gods are demons fully encompasses what demons are for Augustine, and I proceed by elucidating the theology with which he contextualizes this assertion and makes it intelligible. Demons emerge as a highly integrated component of Augustine’s broader theology, having not a merely conceptual but a fully religious significance. The dissertation begins with the intellectual nature of the angels and their Christocentric mission to reveal God in creation. The second chapter considers the fall of the angels and Augustine’s questions about its cause and the timeline of its occurrence. These questions pertain to the matter of embodiment, which becomes the starting point for Chapter 3, where we discuss the demons’ putative aerial bodies, their appearance in bodily visions, and some of Augustine’s reports of wondrous demonic phenomena. These phenomena are identified together as demonic not by a common aerial nature but a common meaning. Chapter 4 begins our analysis of what is the most significant demonic phenomenon for Augustine, viz. pagan religion. There we give an account of Augustine’s notion of the devil’s body, which, like its counterpart in the body of Christ, is constituted by sacraments, whose production is best described in terms of Hermetic “god-making.” The last chapter examines Augustine’s account of pagan sacramental theology more specifically, in terms of both a more straightforward understanding of pagan religion, and the more philosophical one offered by the Platonists. The demons’ association with pagan religion represents the full inversion of the angels’ Christocentric ministry, such that the only true freedom from demons is found, according to Augustine, through incorporation into the sacramental life of the church. / Dissertation / Doctor of Philosophy (PhD) / This thesis gives an account of Augustine’s understanding of demons. Christian Scriptures declare that pagan gods are demons, and I argue this fully encompasses what demons are for Augustine, as they have not a merely conceptual but a fully religious significance. This study explores the theology with which he contextualizes this assertion and makes it intelligible. Demons are a highly integrated component of Augustine’s broader theology, rooted in his conception of angels as the ministers of all creation under God. They take shape through Augustine’s doctrine of evil as privation and understanding of the fall, his thoughts on embodiment, desire, and visions, as well as his theology of sacraments and social bodies. The demons’ association with pagan religion represents the full inversion of the angels’ Christocentric ministry, such that, for Augustine, the only true freedom from demons is found through incorporation into the sacramental life of the church.