In an age of word clouds, topic modeling, text mining, and infinite archives, it’s not surprising that many discussions about digital history focus on the “big” uses of things like keyword searching and digitized texts. For historians, access to huge archives of online text raises important questions about how to read—and how not to read—a million books. Big archives also create exciting opportunities for visualization and text analysis like Building the Digital Lincoln, Rob Nelson’s Mining the Dispatch, and Cameron Blevins’ work on Martha Ballard’s diary.

But with all these exciting new ventures, it’s sometimes easy to lose sight of the fact that simple keyword searches can still offer historians new insights into old sources. One of my most exciting “Aha!” moments (the moments researchers live for) came not along ago when I decided to enter a simple text string from one of Abraham Lincoln’s most famous speeches into the search box on ProQuest’s database of historical New York Times newspapers. I did one search, and got exactly one result. But that was enough to enable me to shed some new light on an old Lincoln quote.

The speech that Lincoln gave in Peoria, Illinois, on October 16, 1854, is significant for many reasons. It marks Lincoln’s return to politics at a time when he was still a little-known free-soil politician whose only experience in national politics had been a short stint in the House of Representatives. The speech detailed Lincoln’s opposition to the Kansas-Nebraska Act and synthesized the arguments that were galvanizing the new Republican Party that would ultimately vault Lincoln into the White House. And it contains some of Lincoln’s most stirring prose about the damage that slavery was doing to the country that he loved.

At Peoria, for example, Lincoln declared that he hated the “zeal” for slavery’s expansion manifested by the Kansas-Nebraska Act. “I hate it because of the monstrous injustice of slavery itself,” Lincoln said, and “I hate it because it deprives our republican example of its just influence in the world—enables the enemies of free institutions, with plausibility, to taunt us as hypocrites—causes the real friends of freedom to doubt our sincerity.” In another of the speech’s most memorable lines, Lincoln warned Americans that “our republican robe is soiled, and trailed in the dust.”

Later, in a crucial and also famous paragraph, Lincoln pressed this claim that slavery was injuring the influence of American republicanism abroad. “Already the liberal party throughout the world, express the apprehension ‘that the one retrograde institution in America, is undermining the principles of progress, and fatally violating the noblest political system the world ever saw.’” This was not the taunt of enemies, Lincoln explained, “but the warning of friends.” He therefore urged Americans to “readopt the Declaration of Independence,” not only to save the Union, but to save it in such a way “that the succeeding millions of free happy people, the world over, shall rise up, and call us blessed, to the latest generations.”

Famous words, these. If you were reading that last paragraph closely, however, you would have noticed that some of the words Lincoln spoke at Peoria were not his own. There are quotation marks in the text of the speech which indicate that one phrase was a quotation from another source. The quoted text reads:

that the one retrograde institution in America, is undermining the principles of progress, and fatally violating the noblest political system the world ever saw

I had long wondered where the quotation came from, but the existing secondary literature on Lincoln sheds no light on the question. The Collected Works of Abraham Lincoln, which are online, retain the internal quotation marks around that phrase, but there is no annotation indicating its source.

So one day last summer, it occurred to me to do a quick search in ProQuest’s database of historical newspapers to see if I could figure out where the quote came from. The result? After a couple of tries, I hit gold with a search for the quote “one retrograde institution” in all newspapers from 1854. I discovered that Lincoln was paraphrasing from an article that appeared in the New York Times on September 29, 1854. And as an added bonus, I also discovered that another famous phrase in Lincoln’s speech—his reference to a “liberal party throughout the world”—was also a paraphrased quotation.

The article that contains these quotes was actually a reprint from the September 12 edition of the London Daily News, which the Times published under the headline, “Mr. Soule’s ‘Vulgar Turbulence’–George Sanders.” It was a long editorial complaining about the recent behavior of two American ambassadors in Europe, who had recently made waves with several brazen attempts to pressure Spain into selling slaveholding Cuba to the United States. First, in 1854, Pierre Soulé had helped author the provocative Ostend Manifesto, and he was accused of trying to wrangle Cuba away from Spain by exploiting the distractions Madrid then faced from threats of internal revolution by liberal reformers. Meanwhile, George N. Sanders, in addition to revealing some anti-republican sentiments in comments he made on the political condition of Switzerland, had recently denounced an antislavery letter published by the Italian revolutionary Giuseppe Mazzini. He had also attempted to persuade Lajos Kossuth, the famous Hungarian revolutionary living in exile in England, to issue a statement dissociating European revolutionaries from the antislavery cause in America.

The appearance of proslavery diplomats like these “in any of the capitals of Europe,” opined the Daily News, “is a symptom of peril which all true Americans should take heed to without the loss of a moment.” It was a powerful point, and to drive it home, the London paper closed with the flourish that evidently caught Lincoln’s attention, whether he read it in the New York Times or in another source:

It will take many years of a virtuous foreign policy, and a long succession of honorable envoys, to remove the apprehensions of the Liberal party throughout Europe that the one retrograde institution in America is undermining the principle of progress, and fatally vitiating the noblest political system that the world ever saw.

So there you have it. When Lincoln cited the opinion of the “liberal party throughout the world” at Peoria in 1854, he was echoing the “apprehensions” of the Daily News and the “Liberal party throughout Europe.”

Knowing this illuminates several other things about the Peoria speech. First, it explains why Lincoln added that the opinion he quoted was not the taunt of enemies to the United States, “but the warning of friends.” As a supporter of the principle of “popular government,” said the Daily News, “we have ever been among the heartiest well-wishers of the Americans” and had “never suffered from those apprehensions of the Republic being destroyed once a year or so, which we have been accustomed to hear of all our lives.” Previous sectional divisions over slavery had never yet shaken these liberal Englishmen’s faith that “our self-governing cousins” would progress to full freedom. But for the first time, the Daily News now feared for the republic’s future. And an ocean away in Illinois, Abraham Lincoln apparently took that newfound fear as an ominous indication of what the zeal for slavery in the United States was doing to the reputation of the world’s model republic and the hopes of liberal reformers abroad.

Second, Lincoln’s citation of the Daily News article provides a fuller context for understanding why he and other Republicans rallied to new action in the summer and fall of 1854. Most explanations of that shift have focused on outrage about the Kansas-Nebraska Act, which was what Lincoln focused on most explicitly in his Peoria speech. But his attention to the article on Sanders and Soulé reveals that Lincoln was also personally angered by the expansionist, proslavery foreign policy of Franklin Pierce’s administration and by the Cuba annexation movement underway at the same time. Indeed, at Peoria, Lincoln explained that one of the most outrageous things about the Kansas-Nebraska Act was that its “prospective principle,” which allowed territorial settlers to decide about the legality of slavery for themselves, would allow slavery “to spread to every other part of the wide world, where men can be found inclined to take it.” Though he didn’t say which parts of the wide world he had in mind, the Daily News article is good evidence that Cuba must have been on his mind as he spoke at Peoria.

Concern about the fortunes of the “liberal party” abroad was not the exception for Lincoln, but the rule. And what this quotation reveals, finally, is that Lincoln understood himself not just as an American, but as a member of a broader “liberal party throughout the world.” In fact, only three years before Lincoln read about Sanders’s efforts to pressure Kossuth to disavow abolitionism, Lincoln had actually served on a welcoming committee in Illinois organized to greet Kossuth on his famous 1851 tour of the United States. That fact is suggestive evidence of Lincoln’s long-standing interest in the fortunes of European revolutionaries and reformers.

Also suggestive is one of the items found among the things Lincoln was carrying on the night that he was assassinated (incidentally, a crime in which the same George N. Sanders was implicated). As Lincoln sat in Ford’s Theater watching a popular English play, there were nine newspaper clippings carefully folded in his leather wallet. And one of them was the report of a speech by the English liberal John Bright, a parliamentary reformer and ardent supporter of the Union cause.

In the speech, Bright spoke of his support for the reelection of Lincoln in 1864 (which indicates Lincoln had been carrying it for some time). Bright’s support must have been gratifying to Lincoln, but perhaps what was most important to the President was Bright’s concluding paragraph:

I believe that the effect of Mr. Lincoln’s reelection in England, and in Europe, and indeed throughout the world, will be this: it will convince all men that the integrity of your great country will be preserved, and it will show that Republican institutions, with an instructed and patriotic people, can bear a nation safely and steadily through the most desperate perils.

Bright’s speech was, on the whole, more optimistic about the fortunes of republicanism abroad than the Daily News a decade earlier. But what both of these clippings had in common—and what evidently made an impression on Lincoln—was their assertion that what happened in the United States had a bearing on the destiny of “Republican institutions” in England as well as “throughout the world.” Knowing that Lincoln read clippings like these, we can conclude that his own powerful rhetoric was informed partly by his attention to what the “liberal party” was saying abroad.

When he expressed his fear that “our republican robe is soiled,” for example, or his hope “the succeeding millions of free happy people, the world over, shall rise up, and call us blessed,” Lincoln gave voice not only to what most Americans liked to believe about the influence of their country, but also to what actual Europeans were saying at the time. And given this fact, it can be misleading to remember the wartime Lincoln as a president who only cared about “the Union” and not at all about “slavery,” as though Lincoln’s Unionism was a sign of pusillanimity instead of moral principle. He cared about the Union partly because he believed the “liberal party throughout the world” was depending on its demonstration that republican institutions were stable and just. And as his Peoria speech reveals, that belief was not separable from his concern about the “monstrous injustice” of slavery.

All of these reflections, remember, were made possible by a simple keyword search. My discovery of the source of Lincoln’s Peoria quote was an incredibly easy discovery to make, thanks to the digitization of the newspaper that contained it. But without that digitization, the article Lincoln cited—buried as it was in one issue of the New York TImes—would have been incredibly difficult to discover. That may be why, as far as I am aware, no other historian has ever identified the quotation’s source, though I would be happy to learn otherwise. Even if it has been noticed before, the important point is that keyword searching was responsible for my finding it for my research, which is one of the reasons why historians should be excited by the digitization of primary sources.

We should be excited, but we should also take an active interest in how that digitization is done. Six years ago, this is the sort of discovery that I dreamed that the keyword revolution would make possible. And I suspect that for most historians, the advantages of the method I’ve used for this post are more familiar and more obvious than the advantages of computer-generated search techniques like algorithmic text mining. But it is worth noting that whether you are text mining, or you are punching in a simple string of text into a search box to discover its source, the size of the corpus you are searching matters a great deal, as does the way that corpus is digitized and made accessible to historians. Experiences like this one remind me of how important it is for historians—even those who don’t define themselves as “digital historians”—to pay attention to issues like the problems with Optical Character Recognition, or Shane Landrum’s caveat lector to users of ProQuest, or Ben Schmidt’s post on what historians don’t know about database design. You may not care a lick about Wordle or know a thing about topic modeling. But if you think it’s useful and interesting to learn who Abraham Lincoln was quoting in one of his most important speeches, these are issues that should matter to you. Increasingly, they matter to me.