Novelty in Byzantium seems a paradox. Yet, in the late twelfth and early thirteenth centuries a visual format emerged that was indeed novel to the Byzantine visual tradition. Displaying the portrait of a saint surrounded by episodes of his/her life in the medium of panel painting, this format, known as the “narrative icon”, soon became a formula. It is also evident in Italy for depictions of that charismatic figure of the duecento – St. Francis. What was the significance of the narrative icon for Byzantium and Italy? How did it relate to the other decisive and lasting visual innovations introduced in the same period in both the Byzantine and Italian contexts? Why did this format continue to flourish well into the post-Byzantine world? This dissertation attempts to answer these questions. In doing so, it emphasises the need to examine the concepts of ‘sanctity’, ‘representation’, and ‘image’ as each was being reconfigured in the twelfth and thirteenth centuries.