ONAMA (http://onama.sbg.ac.at/) – Ontology of Narratives of the Middle Ages – enables the systematic comparison of the structures and building blocks of many narratives in medieval literature and images. This ontology provides a model for a cross-media description of actions, actors, settings and temporal structures. In addition to the constituting basic elements of transmedial “narrative nuclei", these descriptions record the respective textual and pictorial realizations in detail. They thus go beyond the “plot" of a story or picture cycle. ONAMA allows to identify patterns and peculiarities in the construction of narratives, which can then be examined for their underlying causes and functions. ONAMA enables to annotate image and text sources in a way that the generated data provide information about the emergence and transmission of narrative nuclei, figure constellations, patterns of actions, etc. in the respective medium and in cross-media synopses. The ONAMA ontology was developed in the course of the project ONAMA - Ontology of Narratives of the Middle Ages -, which is carried out as an interdisciplinary cooperation between the Mittelhochdeutsche Begriffsdatenbank (MHDBDB) and the Institut für Realienkunde des Mittelalters und der frühen Neuzeit (IMAREAL), both of which are affiliated to the Interdisziplinäres Zentrum für Mittelalter und Frühneuzeit (IZMF) at the University of Salzburg. The project is funded by the go!digital programme of the Austrian Academy of Sciences.