How forty years of arguing over slavery ended with cannon fire in Charleston Harbor, 1820 to 1861
At 4:30 in the morning on April 12, 1861, Confederate guns opened fire on Fort Sumter, a federal fort on an island in the harbor of Charleston, South Carolina. Four years later, about 620,000 to 750,000 soldiers were dead, and by the end of 1865 the 13th Amendment had abolished slavery, freeing about four million people. How did a country that had held together for more than seventy years come to that?
The short answer, and the one the men who led secession gave themselves, is slavery: above all, whether it would be allowed to spread into the West. The longer answer is a chain of compromises, court cases, books, elections and bloodshed, each one making the next compromise harder. This page walks through that chain in order. After the story you will find a clickable timeline, real primary sources with short notes on who wrote them and why, a list of key terms, discussion questions, and a quiz.
A Divided Country
Before the crises, there was the fault line underneath them.
Sectionalism means loyalty to your own region over the nation as a whole. By the 1850s, many Americans thought of themselves first as Northerners or Southerners. The two sections had grown apart in how they made a living, but the deepest difference was a single institution. In the South, about four million people were held as property, and their labor grew the cotton, tobacco, sugar and rice that made the region rich. In the North, every state had passed laws to end slavery by 1804, though “gradual” laws left some people enslaved there for decades. The Northern economy was built on free labor, family farms, growing cities, factories and railroads.
Slavery was not only a Southern matter. Northern mills spun Southern cotton, and Northern banks and shippers profited from it. Most white Northerners were not abolitionists, and racism was common in both sections. What many Northerners did oppose was the spread of slavery into new western territories, which they wanted kept open for free white farmers and workers. White Southern leaders saw any limit on slavery’s expansion as a threat to their wealth, their political power in Congress, and the racial order of their society.
3,953,760enslaved people counted in the 1860 census, nearly all in the 15 slave statesabout 1 in 3Southerners were enslaved in 1860; in South Carolina and Mississippi, more than half the populationabout $3 billionhistorians’ estimate of the market value of enslaved people in 1860 dollars, more than the nation’s railroads and factories combined (some put it at $3.5 billion)
A note on balance. Every new state meant two senators. For decades, Congress tried to admit free and slave states in pairs so that neither side could control the Senate. That is why so many of the fights below are about new territories and new states.
The Road to War
Twelve steps, in order. Watch how each solution plants the seed of the next crisis.
1820Missouri Compromise
The Missouri Compromise
When Missouri asked to join the Union as a slave state, it threatened to tip the Senate. Speaker of the House Henry Clay helped steer through a deal: Missouri entered as a slave state, Maine entered as a free state, and in the rest of the Louisiana Purchase, slavery was banned north of the line of 36°30′ latitude (Missouri’s southern border).
What it changed: For over thirty years the line kept an uneasy peace. But the former president Thomas Jefferson, then 77, warned that the fight had woken him “like a fire bell in the night.” A line drawn on a map along slavery, he feared, would never be erased.
1830sAbolition grows
Abolitionists and the Backlash
In 1831 William Lloyd Garrison began publishing The Liberator, demanding an immediate end to slavery. That same year, Nat Turner led a revolt of enslaved people in Southampton County, Virginia, in which about 55 to 65 white people were killed; in the reprisals, dozens of Black people, many of them not involved, were killed or executed. Southern states responded with harsher slave codes. In Washington, the House adopted a “gag rule” (1836 to 1844) that automatically tabled petitions against slavery without debate.
Formerly enslaved people became some of the movement’s most powerful voices. Frederick Douglass escaped from slavery in Maryland in 1838 and published his Narrative in 1845. Harriet Tubman escaped in 1849 and returned again and again to guide others north on the Underground Railroad.
What it changed: The fight over petitions hardened both sides. Many white Southerners came to see all antislavery talk as an attack on their safety and way of life, while many Northerners saw the gag rule as proof that slaveholders would silence free speech to protect slavery.
1846Wilmot Proviso
War with Mexico and the Wilmot Proviso
The Mexican-American War (1846 to 1848) added a huge area to the United States, including California and most of the present-day Southwest. Before it was even won, Congressman David Wilmot, a Pennsylvania Democrat, proposed that slavery be banned in any territory taken from Mexico. His Wilmot Proviso passed the House more than once but always failed in the Senate.
What it changed: Votes on the Proviso split along sectional lines, not party lines. That was a warning sign. The national parties, which had held North and South together, were starting to crack. A new Free Soil Party formed in 1848 around the idea of keeping slavery out of the West.
1850Compromise of 1850
The Compromise of 1850 and the Fugitive Slave Act
The California Gold Rush brought enough settlers for California to ask to join as a free state, which would break the Senate balance. After months of angry debate, Henry Clay (now a senator) and Senator Stephen A. Douglas of Illinois passed a package of five laws:
California was admitted as a free state.
The Utah and New Mexico territories would decide slavery for themselves (popular sovereignty).
The slave trade (buying and selling, not slavery itself) was banned in Washington, D.C.
Texas gave up land claims in New Mexico in exchange for the federal government paying its debts.
A much stronger Fugitive Slave Act was passed.
The Fugitive Slave Act was the part that came back to haunt the compromise. People accused of escaping slavery could not testify in their own defense and had no right to a jury trial. The federal commissioners who decided cases were paid $10 if they sent the person south and $5 if they set the person free. Northern citizens could be ordered to help with captures, and anyone who helped a freedom seeker faced fines and jail. Free Black Northerners were at risk of being kidnapped into slavery, and thousands fled to Canada.
What it changed: The law brought slavery into Northern towns. Watching armed slave catchers seize people in Boston or Pennsylvania turned many Northerners who had never cared about abolition against the “Slave Power.”
1852Uncle Tom’s Cabin
Uncle Tom’s Cabin
Harriet Beecher Stowe, angered by the Fugitive Slave Act, wrote a novel about the suffering of enslaved families. Uncle Tom’s Cabin first ran in installments in an antislavery newspaper, then came out as a book in March 1852. It sold hundreds of thousands of copies in its first year and became the best-selling novel of the century in the United States. It was banned or attacked across much of the South, where writers answered with novels defending slavery.
What it changed: Millions of Northern readers who had never seen slavery met it on the page, through characters they cared about. A famous story says Lincoln greeted Stowe in 1862 as “the little woman who wrote the book that started this great war,” but there is no reliable record that he said it, so treat it as legend. Today the novel is also criticized for its stereotyped Black characters.
1854Kansas-Nebraska Act
The Kansas-Nebraska Act and “Bleeding Kansas”
Stephen Douglas wanted to organize the land west of Missouri so a transcontinental railroad could run through it. To win Southern votes, his Kansas-Nebraska Act (May 1854) let settlers in the Kansas and Nebraska territories decide on slavery by popular sovereignty. Both territories lay north of 36°30′, so the act in effect repealed the Missouri Compromise.
Northern fury was immediate. Opponents of the act formed the new Republican Party in 1854, dedicated to stopping slavery’s spread. In Kansas, proslavery settlers and “border ruffians” from Missouri and antislavery settlers from the North rushed in, set up rival governments, and fought. In May 1856 a proslavery force sacked the free-state town of Lawrence. Days later, the abolitionist John Brown and his followers killed five proslavery settlers along Pottawatomie Creek. The violence even reached the Senate floor: on May 22, 1856, Congressman Preston Brooks of South Carolina beat Senator Charles Sumner of Massachusetts unconscious with a cane after Sumner gave a speech attacking slavery in Kansas.
What it changed: Letting settlers vote on slavery settled nothing. “Bleeding Kansas” showed that popular sovereignty just moved the fight to the territory and made it armed. Historians estimate that around 50 to 60 people were killed in political violence there (counts vary).
1857Dred Scott
The Dred Scott Decision
Dred Scott was an enslaved man whose enslaver had taken him to live for years in the free state of Illinois and the free territory of Wisconsin. Scott sued for his freedom and that of his family. On March 6, 1857, the Supreme Court ruled against him, 7 to 2. Chief Justice Roger B. Taney’s opinion held that:
Black Americans, free or enslaved, were not citizens and could not sue in federal court;
Congress had no power to ban slavery in the territories, so the Missouri Compromise had been unconstitutional all along.
What it changed: Compromise now looked legally impossible. The ruling seemed to make the Republican Party’s central goal illegal and suggested that no compromise line could ever be drawn again. Many Northerners concluded that a “Slave Power” controlled the government, even the courts. (Scott and his family were freed by a new owner a few months later. Dred Scott died of tuberculosis in 1858.)
1858Lincoln-Douglas debates
“A House Divided” and the Lincoln-Douglas Debates
Running against Douglas for a U.S. Senate seat from Illinois, Abraham Lincoln, a former one-term congressman, opened his campaign with his “House Divided” speech. The two men then held seven debates around the state, mostly about slavery in the territories. Lincoln argued slavery was a moral wrong that must not spread; Douglas defended popular sovereignty. At Freeport, Douglas said settlers could keep slavery out simply by refusing to pass laws to protect it. That answer, called the Freeport Doctrine, angered Southern Democrats.
What it changed: Lincoln lost the Senate race but won a national name. The state legislature (which chose senators then) kept Douglas in office, but the debates made Lincoln a national figure, and Douglas’s answer split his own party.
1859Harpers Ferry
John Brown’s Raid on Harpers Ferry
On October 16, 1859, John Brown led about 20 men, white and Black, in seizing the federal armory at Harpers Ferry, Virginia (now West Virginia). He hoped to arm enslaved people for a revolt. No large uprising came. Within two days, U.S. Marines under Colonel Robert E. Lee stormed the building where Brown was holed up. Ten of his men were killed, including two of his sons. Brown was tried for treason against Virginia and hanged on December 2, 1859.
What it changed: The raid failed, but the fear it caused did not. To many white Southerners, Brown confirmed their worst fear, a Northern plot to start a slave rebellion, and his praise by some Northern writers made it worse. To many abolitionists he was a martyr. Most Republicans, including Lincoln, condemned the raid, but that did little to reassure the South.
1860Election of 1860
The Election of 1860
The Democratic Party, the last major party with strong support in both sections, split in two. Four candidates ran for president:
Abraham Lincoln, Republican: no expansion of slavery into the territories.
Stephen Douglas, Northern Democrat: popular sovereignty.
John C. Breckinridge, Southern Democrat: federal protection for slavery in all territories.
John Bell, Constitutional Union: preserve the Union and avoid the slavery question.
Lincoln won with about 40 percent of the popular vote and 180 of 303 electoral votes, almost entirely from free states. He was not even on the ballot in most of the South. Lincoln had said many times that he would not touch slavery where it already existed. But he had also called it a wrong that must be put “in the course of ultimate extinction.”
What it changed: Lincoln won without a single electoral vote from the slave states, running on a promise to stop slavery’s growth. Southern leaders believed a slavery that could not expand would eventually die, and they would not wait to find out.
1860–61Secession
Secession
On December 20, 1860, a South Carolina convention voted unanimously to leave the Union. By February 1, 1861, Mississippi, Florida, Alabama, Georgia, Louisiana and Texas had followed. In February, delegates met in Montgomery, Alabama, formed the Confederate States of America, and chose Jefferson Davis of Mississippi as president. Last-minute peace plans, such as Senator John J. Crittenden’s proposal to extend the 36°30′ line to the Pacific, failed.
Four states, South Carolina, Mississippi, Georgia and Texas, published formal declarations explaining why they were leaving. They are worth reading, because they answer the “why” question in their own words. All four put the protection of slavery at the center. Excerpts are in the Primary Sources section below.
What it changed: The Union was breaking apart before Lincoln took office. President James Buchanan argued that secession was illegal but that he had no power to stop it, so he did little. By Lincoln’s inauguration on March 4, 1861, seven states had left and seized most federal forts and arsenals within their borders.
1861Fort Sumter
Fort Sumter
Fort Sumter, held by about 85 U.S. soldiers under Major Robert Anderson, was one of the few federal posts in the seceded states still under Union control, and its food was running out. Lincoln chose a careful path: he told South Carolina’s governor he would send only food, not troops or weapons, unless the fort was attacked. Confederate leaders decided not to let that happen. When Anderson refused to surrender, a signal shell from Fort Johnson burst over the fort at 4:30 a.m. on April 12, 1861, and General P. G. T. Beauregard’s batteries opened fire. After about 34 hours of bombardment, Anderson surrendered. No one on either side was killed in the shelling; one Union soldier died, and another was fatally wounded, when a cannon exploded during the salute to the fort’s 33-star flag as the fort was handed over.
On April 15 Lincoln called for 75,000 volunteers to put down the rebellion. Rather than fight against other Southern states, Virginia, Arkansas, North Carolina and Tennessee seceded, making eleven Confederate states. Four slave states, Delaware, Maryland, Kentucky and Missouri, stayed in the Union as border states.
What it changed: Talk had ended and war had begun. The Confederacy had fired the first shot, which united Northern opinion behind the war. The argument over slavery’s future would now be settled by armies.
Timeline: 1820 to 1861
Click or tab to any event and press Enter to open it. Use the buttons to show only one kind of event.
Show timeline events of this type:
Dot colors: law or ruling violence voices and ideas elections and secession
1820 Missouri Compromise law
Missouri admitted as a slave state, Maine as free; slavery banned in the Louisiana Purchase north of 36°30′.
1831The Liberator begins voices
William Lloyd Garrison’s newspaper calls for immediate, total abolition.
1831 Nat Turner’s revolt violence
An uprising of enslaved people in Virginia; Southern states pass harsher slave codes in response.
1832–33 Nullification Crisis law
South Carolina claims it can cancel a federal tariff inside its borders. President Andrew Jackson threatens force; a compromise tariff ends the standoff. The idea that a state can defy federal law is now out in the open.
1836 House “gag rule” law
Antislavery petitions are automatically tabled without debate until the rule is repealed in 1844, largely through the efforts of John Quincy Adams.
1845 Douglass’s Narrativevoices
Narrative of the Life of Frederick Douglass, an American Slave is published and becomes a bestseller.
1846 Wilmot Proviso law
A proposed ban on slavery in land taken from Mexico. It passes the House but fails in the Senate.
1850 Compromise of 1850 law
California enters free; popular sovereignty in Utah and New Mexico; a strict new Fugitive Slave Act.
1852Uncle Tom’s Cabinvoices
Harriet Beecher Stowe’s novel turns many Northern readers against slavery.
1854 Kansas-Nebraska Act law
Popular sovereignty replaces the 36°30′ line. The Republican Party forms in protest.
1856 Bleeding Kansas and the caning of Sumner violence
Lawrence is sacked (May 21), Sumner is beaten in the Senate (May 22), and John Brown’s men kill five at Pottawatomie Creek (May 24–25).
1857Dred Scott v. Sandfordruling
The Supreme Court rules Black Americans are not citizens and Congress cannot ban slavery in the territories.
1858 “House Divided” and the Lincoln-Douglas debates voices
Seven debates in Illinois make Lincoln nationally known; Douglas keeps his Senate seat.
1859 John Brown’s raid violence
Brown seizes the Harpers Ferry armory on October 16; he is captured and hanged on December 2.
Nov. 6, 1860 Lincoln elected politics
Four-way race; Lincoln wins without a single electoral vote from a slave state.
Dec. 20, 1860 South Carolina secedes politics
The first state to leave the Union. Its convention publishes a declaration of causes on December 24.
Jan.–Feb. 1861 Six more states secede politics
Mississippi, Florida, Alabama, Georgia, Louisiana and Texas. The Confederacy forms in Montgomery in February with Jefferson Davis as president.
Mar. 4, 1861 Lincoln’s inauguration politics
Lincoln says secession is illegal, promises not to interfere with slavery where it exists, and pleads for peace.
Apr. 12–13, 1861 Fort Sumter violence
Confederate batteries bombard the fort for about 34 hours until Major Anderson surrenders. The war has begun.
Apr.–June 1861 Upper South secedes politics
After Lincoln’s call for 75,000 volunteers, Virginia, Arkansas, North Carolina and Tennessee join the Confederacy.
What About “States’ Rights”?
You may hear that the war was about states’ rights, or tariffs, and not slavery. Here is how historians weigh that claim.
States’ rights to do what?
Southern leaders did argue that states had the right to leave the Union. But the right they most wanted to protect was the right to hold people as property. The secession declarations say so directly.
They wanted more federal power, too
South Carolina’s declaration complains that Northern states passed laws to block the Fugitive Slave Act. In other words, it objected to Northern states using their rights, and demanded that the federal government enforce slavery in the North.
Tariffs and economics
Tariffs had caused the Nullification Crisis in 1832, and economic differences between the sections were real. But by 1860 tariffs were low. Georgia’s declaration spends a few paragraphs on federal economic policy, then returns to slavery as the main grievance; the others focus on slavery almost entirely.
Where the myth came from
After the war, some former Confederate leaders and later writers recast the cause as states’ rights and honor rather than slavery. Historians call this the Lost Cause interpretation. It shaped textbooks and monuments for generations, but it does not match what secession leaders wrote in 1860 and 1861.
Two things can be true. The North did not go to war in 1861 to end slavery. Most Union soldiers enlisted to save the Union, and Lincoln’s first goal was to stop secession. The South left the Union to protect slavery. Ending slavery became a Union war aim later, with the Emancipation Proclamation in 1863.
Primary Sources
Short excerpts in the writers’ own words, with a note on who said it and why. Spelling, capitalization and punctuation follow the printed sources listed at the bottom of the page.
Some of these sources express racist ideas openly. They are included because they show, in the speakers’ own words, what they were fighting for. Read them as evidence, not as views this page shares.
“…this momentous question, like a fire bell in the night, awakened and filled me with terror. I considered it at once as the knell of the Union.”
Thomas Jefferson, letter to Congressman John Holmes, April 22, 1820
Jefferson, himself an enslaver, is reacting to the Missouri crisis. He feared that a geographic line dividing slave and free states would split the country.
“What, to the American slave, is your 4th of July? I answer; a day that reveals to him, more than all other days in the year, the gross injustice and cruelty to which he is the constant victim.”
Frederick Douglass, speech in Rochester, New York, July 5, 1852
Invited to speak at an Independence Day event, Douglass reminded his white audience that the freedom they were celebrating did not include millions of enslaved Americans.
“…that they had no rights which the white man was bound to respect…”
Chief Justice Roger B. Taney, Dred Scott v. Sandford, March 6, 1857
Taney was describing how he believed the nation’s founders had viewed Black people, to argue they could never be citizens. The phrase was quoted with outrage across the North.
“A house divided against itself cannot stand. I believe this government cannot endure, permanently half slave and half free. I do not expect the Union to be dissolved — I do not expect the house to fall — but I do expect it will cease to be divided. It will become all one thing or all the other.”
Abraham Lincoln, “House Divided” speech, Springfield, Illinois, June 16, 1858
Accepting the Republican nomination for the Senate, Lincoln borrowed a line from the Bible (Mark 3:25) to argue that the country could not stay split on slavery forever.
“I John Brown am now quite certain that the crimes of this guilty, land: will never be purged away; but with Blood.”
John Brown, note handed to a guard on the morning of his execution, December 2, 1859
Brown’s last written words predicted that slavery would end only through violence. (The odd punctuation is Brown’s own.)
“A geographical line has been drawn across the Union, and all the States north of that line have united in the election of a man to the high office of President of the United States, whose opinions and purposes are hostile to slavery.”
South Carolina, Declaration of the Immediate Causes Which Induce and Justify the Secession of South Carolina from the Federal Union, December 24, 1860
South Carolina’s convention names Lincoln’s election, by Northern votes alone, as the final straw. Much of the declaration lists Northern failures to return people who escaped slavery.
“Our position is thoroughly identified with the institution of slavery — the greatest material interest of the world.”
Mississippi, A Declaration of the Immediate Causes which Induce and Justify the Secession of the State of Mississippi from the Federal Union, January 1861
This is the declaration’s second sentence. Mississippi’s leaders state their reason for leaving the Union at the very start.
“Our new government is founded upon exactly the opposite idea; its foundations are laid, its corner-stone rests, upon the great truth that the negro is not equal to the white man; that slavery, subordination to the superior race, is his natural and normal condition.”
Alexander H. Stephens, Vice President of the Confederacy, “Cornerstone Speech,” Savannah, Georgia, March 21, 1861
The “opposite idea” Stephens rejects is the belief, which he says Jefferson and other founders held, that slavery was wrong. The speech survives in newspaper reports, and Stephens later claimed it was reported inaccurately, but this passage was widely printed at the time. Commas vary slightly between printed versions.
“I have no purpose, directly or indirectly, to interfere with the institution of slavery in the States where it exists. I believe I have no lawful right to do so, and I have no inclination to do so.”
Abraham Lincoln, First Inaugural Address, March 4, 1861
Lincoln was quoting from his own earlier speeches to reassure the South. In the same address he called secession illegal and closed with “We are not enemies, but friends.” Compare this with the House Divided speech: how do the two fit together?
Full citations and links to every document are in the Sources section at the bottom of the page.
Key Terms
Words you will see again and again in this unit.
Sectionalism
Loyalty to one’s own region (North, South or West) over the country as a whole.
Abolitionist
A person who wanted to end slavery completely, not just stop it from spreading.
Free soil
The idea that western territories should be closed to slavery and kept for free settlers.
Popular sovereignty
Letting the settlers of a territory vote on whether to allow slavery. Championed by Stephen Douglas.
Fugitive Slave Act
The 1850 law requiring the return of people who escaped slavery, even from free states, with almost no legal protections for the accused.
Underground Railroad
A loose, secret network of people, Black and white, who helped freedom seekers escape to the North and Canada.
Personal liberty laws
Northern state laws meant to protect free Black residents and slow down the Fugitive Slave Act.
“Slave Power”
A phrase Northerners used for what they saw as slaveholders’ control over the federal government.
Republican Party
Founded in 1854 to oppose the spread of slavery into the territories. Lincoln was its first president.
Nullification
The claim that a state could refuse to obey a federal law it considered unconstitutional.
Secession
Formally withdrawing from the Union. Eleven states seceded in 1860 and 1861.
Confederacy
The Confederate States of America, formed by the seceding states in February 1861.
Border states
The slave states that stayed in the Union: Delaware, Maryland, Kentucky and Missouri.
Lost Cause
A postwar interpretation that downplayed slavery and portrayed the Confederacy as fighting for states’ rights and honor.
Discussion Questions
For class or at home. Use evidence from this page, and the primary sources especially, to back up your answers.
Pick the one event on the timeline you think made war most likely. Defend your choice, then explain the strongest argument for a different event.
Several compromises held the Union together for forty years. Were they wise, or did they only delay a conflict and let slavery grow? Could any compromise have worked after 1857?
Read the South Carolina and Mississippi excerpts and the Cornerstone Speech. What reasons do the authors themselves give for secession? How does that evidence affect the “states’ rights” argument?
Lincoln said in 1858 that the country would become “all one thing or all the other,” and in 1861 that he had no purpose to interfere with slavery in the states. Are these statements contradictory? Why might he have said each one?
John Brown has been called both a martyr and a terrorist. What do you think, and what makes the question hard?
How did ordinary people, such as freedom seekers, Underground Railroad helpers, novel readers and Kansas settlers, push national leaders toward or away from war?
Test Yourself
Ten questions on the road to war. Click an answer to check it.
The Road to Sumter
Sources
Where the quotations and facts on this page come from. All the documents quoted are in the public domain.
Frederick Douglass, Oration, Delivered in Corinthian Hall, Rochester (Rochester: Lee, Mann & Co., 1852), the speech now known as “What to the Slave Is the Fourth of July?”
Dred Scott v. Sandford, 60 U.S. 393 (1857), opinion of Chief Justice Taney. Library of Congress, U.S. Reports, vol. 60.
John Brown, handwritten note, Charles Town, Virginia, December 2, 1859, as printed in F. B. Sanborn, The Life and Letters of John Brown (Boston, 1885).
South Carolina, “Declaration of the Immediate Causes…,” December 24, 1860, and Mississippi, “A Declaration of the Immediate Causes…,” January 1861. Yale Law School, Avalon Project: South Carolina, Mississippi. All four state declarations are collected by the American Battlefield Trust.
Alexander H. Stephens, “Cornerstone Speech,” Savannah, March 21, 1861, as reported in the Savannah Republican and reprinted in Henry Cleveland, Alexander H. Stephens, in Public and Private (Philadelphia, 1866). Text at the American Battlefield Trust.
Abraham Lincoln, First Inaugural Address, March 4, 1861. Yale Law School, Avalon Project.
Read the books
Frederick Douglass, Narrative of the Life of Frederick Douglass, an American Slave (Boston, 1845). Free at Project Gutenberg #23.
Enslaved population: U.S. Census Bureau, Population of the United States in 1860 (Eighth Census, 1864).
War deaths: J. David Hacker, “A Census-Based Count of the Civil War Dead,” Civil War History 57, no. 4 (December 2011), which raised the traditional figure of about 620,000 to roughly 750,000.
Value of enslaved people in 1860 (about $3 billion or more, worth more than the nation’s railroads and factories combined): Steven Deyle, Carry Me Back: The Domestic Slave Trade in American Life (Oxford University Press, 2005). Some historians, including David W. Blight, put the figure at about $3.5 billion.
Narrative history: James M. McPherson, Battle Cry of Freedom: The Civil War Era (Oxford University Press, 1988), and the National Park Service and American Battlefield Trust pages linked above.