In this paper, we present the diachronic maps of a selection of 75 Latin modal markers designed through the tool 'Pygmalion'. Both the maps and 'Pygmalion' were conceived in the framework of the 'WoPoss' project, which aims at analysing the diachronic pathways of modality in Latin. While the description of the tool and its functionalities is beyond the scope of this paper, we focus here on the description of our diachronic modal maps. Using visualisations to represent semantic shifts is a well-known practice in some linguistic fields such as typology and lexicography, and they have already been applied to modality. Though the situation is rapidly evolving, typological semantic maps as well as lexicographic maps are still for the most part static and usually not-interactive visualisations. Our modal maps stand out not only for their interactivity, but also for the richness of the information conveyed: chronology, etymology, semantics, syntax, first attestation and diachronic relationships between the meanings. After presenting our conceptual framework for modality, we illustrate the process of conceptualisation and development of our diachronic maps of modality. More specifically, we explain how we gathered and organised the data in order to transpose it into a visual representation. We then showcase the map of 'possum' as an example of our results. Subsequently, we discuss the results with respect to previous literature concerning both visualisation of modal evolution from a general point of view and the investigation of modality in Latin. Finally, we outline possible applications within and beyond the 'WoPoss' project.