Datasets, published as editions
Ortelius treats a map less like an illustration and more like a scholarly edition. Each entry in the catalog — a study — is a self-contained dataset with a fixed provenance, a recommended citation, a DOI, and a live cartographic plate. The corpus is small and curated rather than comprehensive: the aim is that every figure on the page can be traced to its source and recomputed independently.
The atlas currently publishes 22 studies across 4 research domains, totalling 15,034 geolocated records.
Curated data, reconciled and frozen
Source corpora are collected as CSV and hand-checked for completeness and internal consistency. Where possible, named entities are reconciled against Wikidata to attach stable identifiers and harmonise transliterations, and coordinates are verified against published gazetteers. Each published edition is then frozen: the map runs on static data so that a citation always resolves to exactly what a reader saw.
Some studies are illustrative — representative datasets assembled by hand to demonstrate a cartographic mode. These are labelled as such in their provenance, so the catalog never presents a sketch as a survey.
After Abraham Ortelius
The atlas is named for Abraham Ortelius (1527–1598), the Antwerp cartographer who compiled the Theatrum Orbis Terrarum (1570) — generally regarded as the first modern atlas. Ortelius's innovation was editorial as much as cartographic: he gathered the best available maps, credited his sources, and bound them into a single, citable reference work. This atlas borrows that spirit for thematic data.