Palma, CosimoMegyesi, BeátaAntal, EugenMarák, Pavol2025-05-162025-05-1620251736-6305https://hdl.handle.net/10062/109752This paper presents a novel approach to enhancing the analytical power and interoperability of historical cryptology data by transforming the DECODE database into a Linked Open Data (LOD) resource. We introduce a methodology for modeling encrypted historical documents and cipher keys as a knowledge graph, encompassing ontology development, data transformation, and SPARQL-based querying. This integration enables complex queries across domains, encourages collaboration beyond cryptology, and aligns DECODE with broader efforts in digital humanities and open science. By bridging historical cryptology with LOD principles, we offer a scalable framework for enriching specialized research databases through semantic technologies.enAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttps://creativecommons.org/licenses/by/4.0/DECODE databaseLinked Open Datahistorical cryptologydigital historydigital humanitiesArticle