In 1854, Sen. Stephen Douglas forced the Kansas-Nebraska Act through Congress. The bill, which repealed the Missouri Compromise of 1820, also opened up a good portion of the Midwest to the possible expansion of slavery.

Douglas’ political rival, former Illinois Congressman Abraham Lincoln, was enraged by the bill. He scheduled three public speeches in the fall of 1854, in response. The longest of those speeches — known as the Peoria Speech — took three hours to deliver. In it, Lincoln aired his grievances over Douglas’ bill and outlined his moral, economic, political and legal arguments against slavery.

But like many Americans, Lincoln was unsure what to do once slavery ended.

“Lincoln said during the Civil War that he had always seen slavery as unjust. He said he couldn’t remember when he didn’t think that way — and there’s no reason to doubt the accuracy or sincerity of that statement,” explains historian Eric Foner. “The problem arises with the next question: What do you do with slavery, given that it’s unjust? Lincoln took a very long time to try to figure out exactly what steps ought to be taken.”

Foner traces the evolution of Lincoln’s thoughts on slavery in The Fiery Trial: Abraham Lincoln and American Slavery. He explains how Lincoln’s changing thoughts about slavery — and the role of freed slaves — mirrored America’s own transformation.

In the Peoria speech, Lincoln said that slavery was wrong, Foner says, and then admitted that he didn’t know what should be done about it, even contemplating “free[ing] all the slaves, and send[ing] them to Liberia — to their own native land.”

“Lincoln is thinking through his own position on slavery,” says Foner. “[This speech] really epitomizes his views into the Civil War. Slavery ought to be abolished — but he doesn’t really know how to do it. He’s not an abolitionist who criticizes Southerners. At this point, Lincoln does not really see black people as an intrinsic part of American society. They are kind of an alien group who have been uprooted from their own society and unjustly brought across the ocean. ‘Send them back to Africa,’ he says. And this was not an unusual position at this time.”

Foner traces how Lincoln first supported this kind of colonization — the idea that slaves should be freed and then encouraged or required to leave the United States — for well over a decade. Like Henry Clay, Lincoln also supported repealing slavery gradually — and possibly compensating slave owners for their losses after slaves were freed.

It was not until the Emancipation Proclamation, which declared the freedom of all slaves and then named 10 specific states where the law would take affect, that Lincoln publicly rejected his earlier views.

“The Emancipation Proclamation completely repudiates all of those previous ideas for Lincoln,” says Foner. “[The abolishment of slavery is] immediate, not gradual. There is no mention of compensation and there is nothing in it about colonization. After the Emancipation Proclamation, Lincoln says nothing publicly about colonization.”

Foner says many factors led to Lincoln’s shift in his position regarding former slaves. Neither slave owners nor slaves supported colonization. Slavery was beginning to disintegrate in the South. And the Union Army was looking for new soldiers to enlist — and they found willing African-American men waiting for them in the South.

“As soon as the Union Army went into the South, slaves began running away from plantations to Union lines,” Foner says. “And this forced the question of slavery onto the national agenda.”

“Almost from the very beginning of the Civil War, the federal government had to start making policy and they said, ‘Well, we’re going to treat these people as free. We’re not going to send them back into the slave-holding regions,'” Foner says. “And the Army opened itself up to the enlistment of black men. And by the end of the Civil War, 200,000 black men had served in the Union Army and Navy. And envisioning blacks as soldiers is a very, very different idea of their future role in American society. It’s the black soldiers and their role which really begins as the stimulus in Lincoln’s change [with regard to] racial attitudes and attitudes toward America as an interracial society in the last two years of his life.”

Foner is a history professor at Columbia University. He previously has served as the president of the Organization of American Historians, the American Historical Association and the Society of American Historians. His books include Free Soil, Free Labor, Free Man: The Ideology of the Republican Party Before the Civil War and Reconstruction: America’s Unfinished Revolution, 1863-1877. He also appeared as the on-camera historian for the 2003 PBS series Freedom: A History of Us.

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