AbstractThis paper aims to illustrate the abilities and practicability of digital prosopographical databases through the case of historical dates. Numerous historical databases were created in the last few decades, and they applied different models to record and store historical data in an effective way. Although the developers and researchers of these projects faced several problems due to a conflict between the characteristics of structured databases and the nature of historical evidence and historical studies. The paper compares the methodologies of two databases, PBW and RELEVEN through the cases of the death of John of Bari and Bisantius Guirdeliku. The primary sources provide conflicting dates of these events. Thus, the analysis can address the issues of interpretation and authority behind a piece of information.