Despite their profound influence over Byzantine and western cultures of later centuries, the political, theological, and artistic interactions between the East and the West during this period have not yet been investigated in studies combining textual material evidence. By drawing evidence from texts and material culture – some of which have yet to be discussed against the background of the iconoclastic controversy – and by considering the role of oral exchange, assesses the impact of the debate on sacred images and of coeval theological controversies in Rome and central Italy. By looking at intersecting textual, liturgical, and pictorial images which had at their core the Incarnate God and his human mother Mary, the book demonstrates that between 680–880, by unremittingly maintaining the importance of the visual for nurturing beliefs and mediating personal and communal salvation, the popes ensured that the status of sacred images would remain unchallenged, at least until the Protestant Reformation in the sixteenth century.