The TEI/EpiDoc encoding is considered the de facto standard in digital epigraphy as itenables a holistic digital description of an inscription and the semantic mark-up of its text, all of this in a flexible, machine-readable and exchangeable format. At the same time, an EpiDoc document consists of a monolithic, self-descriptive and self-standing information unit which hardly exposes an easy way for cross-linking different documents. This drawback becomes particularly relevant when dealing with material of heterogeneous nature, collected from heterogeneous sources, as it happens in recent content aggregation projects aiming at the construction of a shared Information Space serving a federated community. This is exactly the case for the project EAGLE (Europeana network of Ancient Greek and Latin Epigraphy), whose main aim is to provide a single user-friendly portal to the inscriptions of the Ancient World, a massive resource for both the curious and the scholarly.

Modern search engines enable users to express a great variety of queries against heterogeneous material and provide a rich functionality for users to browse, explore and interlink the items found. To overcome the heterogeneity of the material collected by EAGLE from over 15 different Content Providers, a unifying conceptual model has been defined, and is presented in this paper. The proposed conceptual model, which is based on a preliminary identification analysis based on the CIDOC-CRM ontology, consists of a few core entities which can: i) thoroughly express all the different facets of epigraphy-related content such as physical supports, texts, translations, images and other context-related information; ii) serve as the basis for the definition of a common metadata schema; iii) enable users to express sophisticated queries to accurately retrieve the material of interest.