The Civil War was the deadliest conflict in American history

Between 1861 and 1865, an estimated 620,000 to 750,000 soldiers died from battle and disease—more than in all other US wars combined.

Visualize every day of the American Civil War, in which fighting took place in a majority of the country.

37 maps that explain the American Civil War

This collection of 37 maps tells the story of the American Civil War as well as any historical account. See how and where the war began and why, and where the major battles were fought. Discover how the North achieved victory and the many ways the war changed America forever.

Where was the Civil War fought?

The Civil War is commonly described as a war between northern and southern US states, but where was the war actually fought? Watch this interactive map and timeline to see who fought who and when. Click on specific battles to learn more about each fight.

US westward expansion—and the status of slavery in the new territories—was a major cause of the American Civil War

The addition of new western lands forced the nation to confront whether slavery would spread beyond the South. Each debate over the admission of a new state sharpened the divide between free and slaveholding regions.

Hear how the world reacted to the American Civil War

European nations closely watched the Civil War for its economic and political consequences. Some European nations quietly engaged diplomatically with the Confederacy but withheld recognition. When the Union made slavery's abolition a central cause, European public opinion turned sharply against the South.

Was the Civil War really about states' rights?

The Civil War was fought over slavery, and Confederate leaders and supporters admitted as much in the build-up to the war and after. But later on, after the South's defeat, the lie of the Lost Cause was pushed—and it persists to this day. This four-minute video details the story of the Lost Cause, "state's rights", Confederate monuments, and the machinations behind them.

See rare Civil War photographs preserved by the National Archives

The Civil War was the first major American conflict documented by a camera, with its images distributed widely to the public. The National Archives' digital collection offers thousands of original Civil War images: portraits, battlefields, hospitals, and everyday life.

Two-thirds of soldier deaths during the war were due to disease

Roughly two-thirds of all Civil War deaths resulted from disease rather than battle. Poor sanitation, contaminated water, and limited medical knowledge made camps breeding grounds for dysentery, typhoid, and other deadly infections.

Explore an interactive map of battles from the American Revolution, along with detailed summaries of each engagement.

Abraham Lincoln's election in 1860 triggered a cascade of Southern secessions and the formation of the Confederacy, culminating in the Confederate attack on Fort Sumter in Charleston, South Carolina.

See the army generals who helped define the Civil War

Hear profiles of the Union and Confederate commanders whose choices defined the war's outcome—from Grant and Lee to Sherman, Jackson, and others. See how their actions, tactics, and skills shaped the Civil War.

The Civil War introduced many technological advances to both society and warfare.

The Kansas-Nebraska Act sparked violence that foreshadowed the Civil War

The 1854 Kansas-Nebraska Act let settlers vote on whether to allow slavery, repealing the Missouri Compromise. Competing proslavery and antislavery groups poured into Kansas, sparking years of bloody conflict known as "Bleeding Kansas."

The Civil War turned the Continental Divide into an American symbol of identity

Historians argue that the boundary only became a celebrated American symbol in the 1860s, when Civil War-era leaders promoted a west-east geographic divide to replace the devastating north-south political divide, and that the term's use spiked after the transcontinental railroad crossed it in 1868.

According to Confederate leaders, the defense of slavery was the primary reason for secession.

The Civil War permanently strengthened federal power

The Civil War expanded federal power through emancipation, national military mobilization, and postwar civil rights laws, permanently strengthening the national government and shifting the balance of authority away from the states.

Approximately 180,000 African Americans served in Union forces

About 180,000 Black soldiers—roughly 10% of the Union army—served in the United States Colored Troops after 1863. Despite lower pay and discrimination, they were crucial to the Union victory.

A graphic illustration of death tolls in historical events and wars

Which killed more, the American Civil War or the Korean War? Hurricane Katrina or the Titanic sinking? You’ll be surprised how wrong you are about death tolls.

Abraham Lincoln received only 40% of the popular vote in the 1860 election, highlighting the deep divisions in the country on the eve of the Civil War.

Abraham Lincoln's victory in 1860 sparked Southern secession—even before his inauguration

Abraham Lincoln's election on an antislavery expansion platform convinced many Southerners that their way of life was under threat. Within three months, seven states seceded from the Union—forming the Confederacy—before Lincoln took office in March 1861.

The devastation of the American Civil War led to the establishment of Memorial Day

Tracing its origins to the post-Civil War era, Memorial Day began as local tributes to those who lost their lives in the war. Originally taking place annually on May 30, it was moved to the final Monday in May in 1971.

Nineteenth-century, hand-drawn infographics on US slavery and race

In the second half of the 19th century, researchers studying the behavior of the millions of emancipated Americans after the Civil War used "information graphics" to cut through the noise of racially charged debate. In this collection from Stanford, you can see century-old, stunningly hand-drawn data visualizations showing racial demographics, the effects of emancipation on cotton prices, and more.

In the midst of the Civil War, Lincoln rapidly expanded presidential power

Abraham Lincoln suspended habeas corpus, expanded the army without congressional approval, and issued the Emancipation Proclamation—despite likely lacking authority to unilaterally alter national slave law. His actions set precedents for expanded presidential power in wartime.

Congress descended into fistfights, duels, and violence before the Civil War

In the decades before the Civil War, members of the United States Congress carried weapons, assaulted colleagues, and, in one case, a congressman killed another in a duel. The violence was driven largely by sectional conflict over slavery and foreshadowed the nation's descent into war.

A map of slavery's spread across the US

Need a visual on how prevalent slavery was in the US? Scroll through this interactive map and timeline based on census data from 1790 to 1860.

The Lincoln-Douglas debates sharpened the national divide over slavery

In 1858, Abraham Lincoln and Senator Stephen Douglas debated while competing for an Illinois Senate seat. Their seven debates, reprinted nationwide, brought the question of slavery to the forefront—further polarizing the country and propelling Lincoln to national prominence.

What happened after the Civil War?

After the massive devastation and scorched earth wartime methods of the Civil War, the US entered its Reconstruction era. Listen to this podcast to learn what that entailed and who was affected.

Bills passed during the Civil War shaped postwar America

Despite the war with the South, Congress passed transformative laws like the Homestead Act and the Morrill Land-Grant College Act, which encouraged westward settlement and expanded higher education.

Watch Ken Burns' documentary series on the American Revolution, which tells its story through the lives of soldiers, civilians, enslaved people, Native nations, and international allies.

Explore new and contemporary perspectives with Emerging Civil War

Emerging Civil War brings together historians and writers who offer fresh research, essays, and battlefield stories that uncover overlooked events, people, and places—showing that scholarship on the war is still evolving over 160 years later.

Listen to firsthand accounts of how Black Americans fought to end slavery and shape Reconstruction

This podcast explores the actions of Black Americans who fought for freedom before, during, and after the Civil War—highlighting their key role in abolition and the Reconstruction era.

The Mexican-American War trained future Civil War generals

Many key military leaders of the Civil War—including Ulysses S. Grant, Robert E. Lee, and Thomas “Stonewall” Jackson—first saw combat in the Mexican-American War, gaining battlefield experience that shaped their later commands.

How Emily Dickinson and Walt Whitman grappled with the American Civil War

Whitman, whose brother was injured while fighting for the Union, was often overt in his pro-Union poems. Dickinson, whose brother paid to have someone enlist under his name, was more subtle, though equally as affected, as this comparative analysis makes clear.

Hear firsthand stories from the Civil War

Historian and storyteller Fred Kiger narrates detail-rich episodes exploring overlooked people and moments of the Civil War—bringing listeners onto battlefields and into strategy rooms and offering insight into the lives of those who lived the conflict.

US troops committed widespread atrocities during the Mexican-American War

American volunteer regiments frequently looted towns, raped civilians, and executed prisoners—especially in occupied northern Mexico. Historians have documented how racial hatred and impunity fueled war crimes that were rarely punished by military leadership.

Abolitionists shaped American history from the Revolution to the Civil War

Abolitionists of all backgrounds organized against slavery from the founding era onward. Historian Manisha Sinha argues that their decades of activism fundamentally shaped American democracy and made emancipation possible.

The Union victory at Gettysburg marked a major turning point in the war

Fought July 1-3, 1863, the Battle of Gettysburg ended the Confederate invasion of the North. While the Union lost nearly 23,000 troops, its victory in one of America's most famous battles shifted the war's momentum decisively toward the North.

Read an annotated 1866 essay by abolitionist Frederick Douglass, where he laid out his vision for reshaping America after the Civil War.