The data
Everything the atlas draws comes from the files below, served from this folder exactly as the atlas reads them. They are built from Wikidata and the open research datasets named beside each, by the scripts in the atlas’s repository, and rebuilt when a source or a reading changes. Data built 2026-10-06, release v2.8.0.
38,415 rows: 3,291 states, 11,299 events, 22,392 people and 1,433 works; the rulers of 1,974 states in order; 14,966 border polygons over 1,466 states; 1,588 cities; 184 trade routes; 10,726 hazards; 11 theories. The same numbers are at numbers.json.
Using it
- Every file is fetched by address, with open CORS, so a script or an agent can read it from anywhere.
- Each file carries its source’s licence, named below; the sentences quoted from Wikipedia make a file CC BY-SA 4.0.
- The published atlas and its data are offered for non-commercial use, because two of its layers (the ethnic groups and the cultural regions) are licensed so; the code is GPL-3.0.
- A view of the atlas is addressed by its query string and reproduces exactly: cite it by its address. A machine starts at /llms.txt.
- Years are the historian’s: negative is BCE and there is no year 0. A date is kept at the precision its source gave.
The files
| File | What it holds | Source | Licence | Size |
|---|---|---|---|---|
| entities.json | Every row of the atlas: id, kind, name, dates and their precision, place, region, domain and category, Wikipedia language editions, the English article’s title, the state it belongs to and how that was decided. | Wikidata, with the atlas’s own curated rows | CC0 1.0 | 13.7 MB |
| relations.json | Every recorded statement linking one entity to another, with the property and its direction, and what is known about the things the atlas does not hold. | Wikidata | CC0 1.0 | 14.7 MB |
| reigns.json | Who held each state’s highest office, in order, with the dates each term carried; the heads of government and the formal heads of state beside them; the collegial offices. | Wikidata; for states it names no ruler of, the lines English Wikipedia’s infoboxes give | CC0 1.0 (facts read from Wikipedia credited to it) | 2.9 MB |
| merged.json | The ids of states merged into another, so an old link opens the kept row. | The atlas | The atlas’s own, derived; for non-commercial use | 0 KB |
| meta.json | When the data was built, the row count, the floors each query applied. | The atlas | The atlas’s own, derived; for non-commercial use | 1 KB |
| numbers.json | The counts this site prints about itself, read from the files above at build. | The atlas | The atlas’s own, derived; for non-commercial use | — |
| images.json | A portrait per person and a flag or crest per state, as a Wikimedia Commons file name and hash path. | Wikimedia Commons | Each file’s own, on its Commons page | 2.4 MB |
| flags.json | Every flag and coat of arms each state had, with the years it flew, the Commons file, its licence and its author. | Wikidata and Wikimedia Commons | Each file’s own, listed in the file | 282 KB |
| facts.json | How each war, battle, rising and coup ended and how each state fell, read from its own article by grammar, one sentence each. | Wikipedia | CC BY-SA 4.0 | 303 KB |
| causes.json | The sentences in an article that state a cause or a result, bound to the page’s subject by grammar. | Wikipedia | CC BY-SA 4.0 | 1.5 MB |
| mentions.json | Every atlas entity an article names, with the sentence and the section. | Wikipedia | CC BY-SA 4.0 | 19.9 MB |
| claims.json | The atlas’s own causal claims, each with the historians for and against it. | The atlas, citing published works | The atlas’s own, derived; for non-commercial use | 59 KB |
| mechanisms.json | Eleven instability mechanisms from the comparative literature, evaluated over every outcome event and every state-year. | The atlas, reading V-Dem among others | CC BY-SA 4.0 | 1.9 MB |
| cities.json | 1,588 cities with population estimates from 2250 BCE to 1975, each under the name it had in each period. | Reba, Reitsma & Seto 2016 (Chandler, Modelski); names the atlas’s own | CC BY 4.0 | 397 KB |
| routes.geojson | 184 curated trade corridors with their goods, phases and volumes. | The atlas | The atlas’s own, derived; for non-commercial use | 287 KB |
| roads.geojson | 3,165 Greek and Roman road segments. | Ancient World Mapping Center (Barrington Atlas) | ODbL 1.0 | 928 KB |
| peoples.geojson | 1,665 named peoples and ancient regions, 750 BCE – 640 CE, dated by Pleiades. | AWMC linework, Pleiades dates | ODbL 1.0 / CC BY 3.0 | 461 KB |
| pleiades.json | 15,876 settlements, forts and shrines of the ancient world, located and dated. | Pleiades | CC BY 3.0 | 838 KB |
| ethnic.geojson | 885 ethnic groups of the 1964 Atlas Narodov Mira, drawn across 1900–2030. | GREG (Weidmann, Rød & Cederman) | Research and teaching, with citation | 3.1 MB |
| tribes.json | The approximate ground of the Slavic peoples the atlas files as states, drawn from the rivers their sources name. | The atlas, set against SeikoEn’s map (CC BY-SA 3.0) | The atlas’s own, derived; for non-commercial use | 31 KB |
| migrations.geojson | Eight movements of peoples, curated with their basis. | The atlas | The atlas’s own, derived; for non-commercial use | 10 KB |
| piracy.json | Which rows belong to the piracy collection. | The atlas | The atlas’s own, derived; for non-commercial use | 13 KB |
| regions.json | The six world regions’ bounding polygons and the lane order. | The atlas | The atlas’s own, derived; for non-commercial use | 6 KB |
| lenses.json | The registry of every dataset the research layer can read, with its window and its licence. | The atlas | The atlas’s own, derived; for non-commercial use | 13 KB |
| plate.json | The map’s plate: land, lakes and rivers at 1:50m. | Natural Earth | Public domain | 1.8 MB |
| seshat.json | Structural variables per state - its elite, its government, its revenue - 4000 BCE to 1900. | Seshat Global History Databank | CC BY-SA 4.0 | 853 KB |
| borders/ | Historical political borders in fourteen bands, 3400 BCE – 2024, simplified for the map, with a label point per polygon; index.json lists the bands. | Cliopatria (Seshat Global History Databank) | CC BY 4.0 | 57.7 MB |
| series/territory.json | The area in km² each state held, as a step series per year, on an equal-area projection. | Computed from Cliopatria’s borders | CC BY 4.0 | 173 KB |
| series/rulers.json | How each ruler died, Wikidata’s own end cause on each term, what each successor was to the predecessor, and each ruler’s portrait. | Wikidata | CC0 1.0 | 990 KB |
| series/exits.json | How each ruler left office and came to it, read from their article by grammar, with the sentence. | Wikipedia | CC BY-SA 4.0 | 983 KB |
| series/elites.json | Succession instability per state per century, derived from the lines of rulers and the atlas’s own violent rows. | The atlas | The atlas’s own, derived; for non-commercial use | 1.6 MB |
| series/monarchs.json | 723 reigns in 27 European monarchies, 1000–1799: who was deposed or killed, civil wars, parliaments. | Kokkonen, Krishnarajan, Møller & Sundell 2021 | CC0 1.0 | 124 KB |
| series/nobility.json | Per state and half-century: the people Wikidata records as citizens, how many carry a noble title, how many held an office. | Wikidata | CC0 1.0 | 124 KB |
| series/vdem.json | What the chief executive’s power rested on, five ways, and coups, 1789 on. | V-Dem v16 | CC BY-SA 4.0 | 148 KB |
| series/economy.json | GDP per capita and population of modern territories, 1–2022. | Maddison Project Database 2023 | CC BY 4.0 | 501 KB |
| series/hazards.json | 10,726 earthquakes, eruptions and tsunamis, placed in the state whose borders held them. | NOAA NCEI | Public domain | 2.3 MB |
| series/drought.json | Tree-ring summer moisture for Europe and the Mediterranean, 0–2012, on a 5° grid. | Old World Drought Atlas | Public domain | 1.0 MB |
| series/volcanic.json | Volcanic sulfur injections from ice cores. | eVolv2k / HolVol | CC BY 4.0 | 45 KB |
| ground/ | Land use at every step from 3000 BCE, biomes and rainfall every 1,000 years, as indexed pictures; ground.json carries the shares, the temperature reconstructions and the climate episodes. | HYDE 3.2.1; Beyer, Krapp & Manica 2020; PAGES 2k, Neukom et al., Kaufman et al. | CC BY 3.0 · CC BY 4.0 · public | 2.7 MB |
| underlay/ | The optional cultural-regions underlay. | aourednik/historical-basemaps | GPL-3.0 | 5.1 MB |
The full licence notes, with every source’s terms and what was done with each, are in the atlas’s LICENSES file; the How-to page inside the atlas lists the same sources for readers.