From Stones and Wells to Tephra: Leveraging Wikidata and Wikibase for Interdisciplinary Humanities Linked Data

This discussion paper examines how Wikidata and related Wikibase infrastructure can serve as an active integration layer within a Federated Knowledge Graph Ecosystem (FKGE) for the humanities. Using three case studies – Irish Ogham Stones, Irish Holy Wells, and Campanian Ignimbrite (CI) findspots – we illustrate how heterogeneous sources can be semantically harmonised and connected across disciplinary boundaries without centralising the underlying datasets. The Ogham case links epigraphic resources from established scholarly corpora and digital editions to Linked Open Data (LOD), Wikidata, and OpenStreetMap, showing how curated reference data can be enriched through community curation while retaining explicit bibliographic provenance via Wikidata references. The Holy Wells case demonstrates citizen-science documentation of vernacular religious heritage, modelled as structured statements in Wikidata and made interoperable through semi-automated mappings to CIDOC CRM. The CI case integrates geoscientific and archaeological evidence through a dedicated fuzzy-sl Wikibase and the Fuzzy Spatial Locations Ontology (FSL-O), enabling the representation of spatial uncertainty, measurement precision, and provenance across domains. Across all three cases, interoperability is achieved through shared identifiers, ontology alignment, and FAIR/FAIR4RS-oriented workflows, supported by open repositories and versioned transformation scripts. The paper argues that Wikidata is best understood not only as a data source but as a semantic and social infrastructure in which modelling conventions, attribution practices, and reuse pathways are negotiated within an open, federated ecosystem.