Summary: The proposed study investigates the information needs and information-seeking behavior of archival users. For this purpose the ARGUS information system of the German Bundesarchiv and related reference questions are analyzed in a case study in order to model patterns of questions and search behavior in an ontology. This knowledge graph represents the knowledge archival users expect from archival finding aids. It is being compared with the knowledge graph of archival finding aids encoded with the Encoded Archival Description (EAD) standard in order to identify semantic gaps. The aim is to find out if information modeled in EAD matches the archival user’s expectations and to formulate a model and methodology which can be applied and validate in similar cases of digital archives in order to improve and facilitate access to archival information systems.