Why Computational Historians Need Wikidata
Over the past several months I extracted several hundred thousand biographical statements from two Victorian reference works, the Colonial Office List and the India Office List, printed almost every year from the 1860s into the 1960s. Each volume reprints terse career notices for the men who staffed two civil services: where they were born and schooled, every posting and promotion, every honour. The raw material was a mess of the kind historians know well. The same official recurs in forty annual editions, his notice growing a line at a time; the OCR still garbles the occasional name; two different men who share a surname, one in each service, threaten to collapse into a single phantom career. What turned that pile into a usable dataset, roughly 46,000 distinct officials and some 300,000 dated career events, was grounding it to Wikidata. Its shared identifiers let me structure the notices into typed facts, recognise the same man across editions and across both services, and tell two different officials apart. I did this only because my own atlas needed it. But grounding has a public side effect: it turned my prose into linked open data that anyone working on a neighbouring subject can build on. Most historians do not ground their data yet, and that is what this post is about. If we all start using Wikidata unique identifiers to ground our data, we start collaborating at scale without needing to schedule a single meeting or apply for any grants.
A few digital humanities scholars have been saying that linked open data is the right idea for historical research for fifteen years, and it has under-delivered on its promise. The reason isn’t that the standards were wrong or the vision was misguided. It’s that the practical cost of grounding unstructured historical sources to shared identifiers was too high. Grounding, in this context, means linking the people, places, organizations, and concepts named in your sources to permanent identifiers that other researchers also use, so that your “Philip Wodehouse” and my “Philip Wodehouse” are demonstrably the same colonial governor, not just the same string of letters. You either invested in hand-curating those links and stayed small, or you skipped the work and produced a dataset that couldn’t talk to anyone else’s. Most of us did the second thing.
Two Services, One Empire: career transfers of British colonial and India Office officials, from the 1820s to the 1960s, drawn from the interactive atlas. Every arc lands where it does because the place was grounded to Wikidata.
That constraint is loosening. Large language models combined with retrieval against Wikidata, the open identifier system that now contains over 120 million items, including millions of historical figures and places, make grounding tractable at the scale of a single researcher with a corpus. The bottleneck has moved from labor to judgment. The clearest way to show what that buys is the part of my own project that should have been hardest: putting every posting on a map.
An atlas built on borrowed coordinates
The structured corpus became an interactive atlas of imperial careers, which plays the more than twenty-two thousand recorded moves between one colony, presidency, or province and another out across a map and through time. To draw a single arc on that map, I needed a latitude and longitude for every place an official was ever posted to. That is the part historians underestimate. The places in these volumes are not modern cities with tidy coordinates. They are nineteenth-century polities: the Colony of Victoria, the Central Provinces, Baluchistan, British Guiana, a princely state like Jodhpur or Chamba. A modern gazetteer either does not contain them or quietly mislocates them to whatever shares the name today.
Wikidata solved this almost for free, and it solved it in two ways. Many of the places I named carry a coordinate location directly, so grounding the surface string to the right Wikidata item handed me the coordinates in the same step. The polities that do not carry their own coordinates almost always link to the place that does: their capital. British Raj resolves to Calcutta and then Delhi; Canada to Ottawa; a princely state to its seat. Once each place in my vocabulary was grounded to a QID, a single query returned coordinates for the entire set, either from the item itself or from its capital. Weeks of manual gazetteer work that I had budgeted for never happened. The technical specifics of how the grounding pipeline disambiguates against millions of candidates, and how I kept the model from inventing identifiers, are in a companion working paper; the point here is the result. The map exists because the coordinates were already in the commons, attached to identifiers I could borrow.
It is worth pausing on how different this is from how I used to work. Trading Consequences, a project I was part of in the early 2010s, processed ten million pages of nineteenth-century commodity sources and located the places in them with the Edinburgh Geoparser, a deterministic system built on a fixed gazetteer. It was the right tool at the time and the team was strong. It was also brittle in the ways historical sources punish: a modern gazetteer, poor OCR, ambiguous toponyms. That took a two-year grant and a big team. The atlas took one historian, Claude Code, and a method that leans on Wikidata for the part that used to be the bottleneck.
What individual scale costs us
Computational history is now possible for individual scholars without grant-funded labs. That is the headline most readers take away, and it is correct. The harder question is what we do with the freedom.
Coding agents are empowering thousands of historians to build new datasets, but this risks a flourishing of data silos. If we all assign different identifiers to distinguish Victoria the Queen from Victoria, British Columbia, we end up rebuilding the same disambiguation work in every project, and losing the chance for our datasets to compose into anything larger than themselves.
This is the problem linked open data was designed to solve. The idea is straightforward: if every dataset attaches the same persistent identifier to the same entity, then datasets compose. Wikidata has already done much of this work, and my own place vocabulary shows why that matters. Take “Victoria,” a posting that turns up constantly in these volumes. It might be the Colony of Victoria an official governed, Victoria in British Columbia he was transferred to, Victoria on Hong Kong Island, a district at the Cape, or a station on Lake Victoria, before we even reach the queen the rest were named for. String matching cannot tell these apart, and a wrong guess drops an official’s whole career in the wrong hemisphere. Wikidata has already done the disambiguation: each Victoria is a distinct item with a permanent identifier, and the colony, which carries no coordinates of its own, points to its capital at Melbourne, which does. Grounding the right Victoria is what put each posting in the right place.
My atlas already shows what composition buys. It surfaces 178 officials who served in both the colonial and the Indian services, the kind of figure who falls between two literatures because no single archive holds the whole career. Philip Edmond Wodehouse is one of them: Governor of British Guiana, then Governor of the Cape Colony, then Governor of Bombay. A historian of the Cape and a historian of British India are unlikely to know each other’s work; their archives are in different buildings and their conferences do not overlap. But if both ground their data to Q1800510, their datasets join automatically. A query about Wodehouse’s career reaches across one historian’s records in Cape Town and another’s in Bombay, without either of them having planned for the integration. The promise of computational history is not that everyone produces their own dataset. It is that many small datasets compose into a research commons larger than any of them.
Ground, do not host
There have been concerns in our community about using Wikidata as scholarly infrastructure, and the worry has a real history. Wikidata is crowdsourced; its data model is determined by its community of editors; some of its modeling decisions, the handling of gender is the canonical case, have been incompatible with the priorities of researchers working on people whose lives the standard categories misrepresent. The response, in projects like LINCS (Linked Infrastructure for Networked Cultural Scholarship), was to build proper scholarly infrastructure with controlled vocabularies, considered ontological commitments, and editorial accountability. Those choices were correct, and I remain hesitant about building knowledge graphs on the Wikidata platform.
But the worry applies to hosting scholarship on Wikidata: treating Wikidata itself as the place where your conclusions live, where your interpretations are subject to revision by anyone who edits the relevant pages. It does not apply to grounding scholarship to Wikidata, which is a different operation entirely. LINCS already works this way. The graph LINCS publishes is its own linked open data, carefully modelled, with editorial accountability to the scholars who contribute to it. It uses Wikidata QIDs directly as the identifiers for entities Wikidata already covers, and mints its own only when no alternative exists. The model is sovereign; the identifiers are shared.
That is exactly the line my atlas walks. The career graph behind it is mine: my OCR, my extraction, my judgments about which biography matches which annual record. Wikidata never sees it. What I took from Wikidata was the identifiers, and through them the coordinates. The data is sovereign; the entities are addressable. This implies periodic verification rather than set-and-forget: QIDs are durable, but the data behind them can be merged, split, or revised, and grounding is a relationship that needs occasional maintenance.
The reason this matters is that the alternative does not scale. No scholarly project, however well-funded, can produce identifiers and coordinates for over 120 million historical people, places, organisms, events, and concepts on its own. Wikidata has done that work. Its coverage is uneven and its modeling has problems, but it is the only system at the right scale for historical research as actually practiced. Ignoring it produces silos. Grounding to it, while keeping your own dataset, is the move that gets us out of this.
Teamwork without teams
The conventional model assumes that data-intensive history requires a team: a principal investigator, a postdoc, a developer, a project manager, a grant. That model still works for some projects, and the funding agencies are organized around it. But the recent shift means a great deal of useful work can now happen at an individual scale. The question is whether that individual work is connected to anyone else’s.
If we ground our work to shared identifiers, it is. A historian working on Bengal in 1850 and a historian working on Jamaica in 1840 do not need to coordinate, share infrastructure, or even know each other to produce datasets that interoperate. They need to use Wikidata identifiers for the people, places, and institutions in their sources. That is teamwork without a team, and it is exactly the kind of distributed, low-overhead collaboration historians have always done at the level of citation and footnote, now extended to structured data.
This is not a call for centralized infrastructure. It is the opposite. It is a call for a small set of shared conventions: use shared identifiers; ground to Wikidata; create new Wikidata entries when the substrate is thin. This lets individuals and small groups produce work that connects to a research commons without anyone having to build the commons explicitly. The commons is the consequence of the convention.
What this requires
Three things, and they are small.
Add Wikidata identifiers to the entities in your datasets. If you have a spreadsheet of historical figures, add a column for their Wikidata identifier. If you cannot find an identifier for an entity, create one. The lift is hours, not weeks, and the tools to do it are now within reach of any researcher with a corpus.
Publish your data with the identifiers attached. A project website, a Zenodo deposit, a GitHub repository: the venue matters less than the principle that the identifiers are present and durable, so that someone reading your work in ten years can still find them.
Treat Wikidata-editing as part of historical practice. When you find that a colonial administrator, a rural township, or an eighteenth-century concept lacks an entry, contribute one with sources. We need to make this an evolving standard of methodological rigor, on the same continuum as proper archival citation: a small permanent addition to the substrate that makes everyone else’s work more findable, including yours.
The technology has changed. Computational history at an individual scale is real now; my atlas is one ordinary historian’s proof of it. Whether the field produces a research commons or a thousand silos depends on whether we adopt shared identifiers. We can. The conventions are small enough that no one needs permission, and large enough that they would change the field.




The promise of true interoperability in the all-too-often fractured edifice of historical knowledge is certainly exciting. I will be linking my datasets to Wikidata in the future before publishing them. I also have to say that your 'Two Services, One Empire' visualisation is simply awesome; I must have watched it 10 times! I'd be very interested to hear more about the AI pipeline that I assume is powering this major project in the background. One question that has lived with me for some months now, from the inimitable Javier Cha, is: "Can we use AI not only to achieve greater breadth but also greater interpretative depth?" Is automation pushing us to macroscopic perspectives?