Wikipedia can be a very diverse working environment. Editors on the English-language Wikipedia will likely interact with many native English speakers from several countries as well as many Western Europeans and others from throughout the world. But the diversity in our editing population as well as in our content has some major gaps. The best known gap is with women editors. About 20% of our editors are women. They represent slightly over half the world's population. About 0.5% of American editors are African-Americans. They represent 13% of the American population.

February is Black History Month in the US. How can we all help document Black history on Wikipedia over the next month?

In an extraordinary article this month, The Washington Post documents that 1,766 congressmen (including male senators), and one female senator, Rebecca Latimer Felton, at some point in their lives claimed to legally own human beings as their slaves. The data collection is ongoing. The original totals were reported as 1,715 slaveholders, 677 not listed because the Post did not have enough evidence to make a conclusion, and 3,166 non-slaveholders. The Post is now asking for crowdsourced contributions – to be checked by reporters – to gather further evidence.

Most of the enslaved people were of African descent. Others were from Native American tribes, or possibly Hispanic. While the general story of congressmen owning slaves has been known since the first congress met in 1789, the Post names 1,767 of them in a detailed table. The evidence was gathered mostly from U.S. Census records but also included wills, journals and other historical documents.

Some of the detailed stories are horrific. Maryland representative John T.H. Worthington, who represented the Baltimore area, claimed ownership of 29 people in the 1840 Census. According to the Post, "He sold his own enslaved daughter for $1,800 to a man who wanted her to bear more enslaved children, according to an account written by James Watkins, who managed to escape slavery." She "refused to consent to sex with her new enslaver. As punishment, she was beaten to death."

The slaveholdings of some congressmen were not generally known until now. The Post cites the Wikipedia article on the senator from New York, Rufus King, a signer of the Constitution, to show this lack of detailed knowledge. Wikipedia did not say that King was a slaveholder, though he owned slaves early in his life and was an anti-slavery activist later. The Post's point was not that Wikipedia is inaccurate – just that the extent of congressional slaveholding is not generally known. But clearly, there are some articles we need to revise.

One indication of our omissions is that our category of American slave owners includes about 1,010 individuals (842 in the main category, about 168 in subcategories). That includes congressmen and non-congressmen alike. Wikipedia includes articles on all U.S. Congress persons since 1789, so at least 756 congressmen are missing from the broader category.

After examining only a few individual articles, I am convinced that many of our articles just don't mention a congressman's slaveholding status, while others distort or don't properly document it. Four examples, where The Post identifies the congressman as a slaveholder, follow.

• Richard Bland Lee was the brother of "Light Horse" Harry Lee of the famous Lee family. Richard owned a large plantation in Fairfax County, Virginia. He won election to the first congress with the help of George Washington's vote. The text of the Wikipedia article on Lee does not have any mention of slaves or slavery, though a template and a category below the text indicates that he owned slaves.
• Daniel Smith brought slaves with him from Virginia to Tennessee to work his 3,000 acre plantation Rock Castle. In his will he bequeathed slaves to several relatives. He served parts of two senate terms. According to an article linked by the Post, about 37 graves of enslaved people remain near his historic home. Neither the Wikipedia biography, nor a longer bio of Smith which is part of the Rock Castle article, include either the words "slave" or "slavery".
• Augustin Smith Clayton. The Wikipedia article on this Georgia representative covers his education, and the stops on his political, judicial, and business careers. The words "slave" or "slavery" are only mentioned once "In 1837 he delivered an address ... (which) criticized the cause of abolition of slavery."
• John C. Calhoun was the leading politician of the Antebellum South, and leading spokesman of the slaveholders' cause, serving as U.S. vice-president, secretary of state, secretary of war, senator and representative from South Carolina over a forty year career. He also owned two large plantations. The article in Wikipedia is a featured article. It is full of his political and philosophical pronouncements on slavery. It states, without a reference, that he "owned dozens of slaves in Fort Hill." One reference – just a single reference in the rest of the article – documents that he owned slaves. It is in a section about the removal of a statue of Calhoun during the 2020 Black Lives Matter protests. The headline of a local television news story – just the headline with nothing on slave ownership in the body of the story – identifies Calhoun as a slave owner: Downtown Charleston protest over statue of slave owner, former Vice President gets heated.

We have a lot of work to do.

Since February is Black History Month, let's get started now. There are a few resources that should come in handy,

• The Washington Post data is available here.
• A list of congressmen that the Post needs more information on is here.
• An incomplete proposed list article is at User:Smallbones/List of U.S. congressional slaveholders

You might first pick a congressman from one of the two lists from the Post, then read the Wikipedia article on the congressman. If you check the proposed list article first and record your work there when you are finished with your editing session, you may avoid duplicating work with other editors.

Is the article well written and well referenced? Does it mention slaves or slavery? You should search for other information on the congressman with an emphasis on the topic of slavery. If possible, search offline in a library's local history collection or at a local historical society. Then make any needed changes. For example you might remove material that supports the discredited "Lost Cause" school of Confederate history. Be particularly careful of potential copyright violations. These were more common in the early years of Wikipedia when many of the articles were written. At the same time, you should remember that most of these articles were based on the Biographical Directory of the United States Congress, which is in the public domain.

If justified by the article content you might then copy and add this footnote:

<ref name="WaPo 012022">{{cite news |last1=Weil |first1=Julie Zauzmer |last2=Blanco |first2=Adrian |last3=Dominguez |first3=Leo |title=More than 1,700 congressmen once enslaved Black people. This is who they were, and how they shaped the nation. |url=https://www.washingtonpost.com/history/interactive/2022/congress-slaveowners-names-list/ |access-date=30 January 2022 |publisher=[[Washington Post]] |date=20 January 2022}}</ref>

Take your time. You won't usually be able to do all this in one editing session. But it is straightforward editing that any experienced editor should be able to do.

There are other ways we might be able to add this information to Wikipedia. For example we could create a category for all slaveholding congress persons, perhaps Category:U.S. congress persons who owned slaves.

While completing this article, I was informed that Wikidata now has an almost complete list. Using

• Q10076267 = slaveholder
• Q13218630 = United States representatives (ie. House) and
• Q4416090 = United States senator

This database query will generate a list of 1,718 congressmen.

This development may be quite important. The identities of congressmen-slaveholders are now available for use in Wikipedia articles and by anybody who knows how to use Wikidata. Adding the attribute "Q10076267 = slaveholder" is allowed for other government figures as well, including presidents, vice-presidents, supreme court justices, cabinet members, ambassadors, generals, admirals, governors, and anybody else with a Wikipedia article about them. These additions to Wikidata could open up and document the whole slaveholding structure of the antebellum republic.

I'll leave further explanation to editors who are more experienced in Wikidata.

An unusual way to help Wikipedia would be to help the Washington Post complete their dataset through crowdsourcing. Julie Zauzmer Weil, the lead author of the Post article, notes that everybody who can do careful research is invited to contribute material to their effort – and that the material will be checked by their reporters.

She told The Signpost "I have been a great admirer of Wikipedia for a very long time. I am sure (the Wikipedia) community of skilled and principled researchers would be marvelous helpers if they are up for the task of looking for evidence about whether any of these congressmen I'm still researching were ever slaveholders."

Let's do it!