11 states formed the Confederacy, with 2 others claiming allegiance

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.

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

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.

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.

The South was placed under federal military rule during Reconstruction

Beginning in 1867, the Reconstruction Acts divided 10 former Confederate states into five military districts, each governed by a Union general. Federal troops supervised elections, enforced civil rights, and maintained order under direct congressional authority.

Despite the Juneteenth announcement that they were free, some enslaved people were still held captive.

Most Confederate soldiers and leaders after the Civil War were pardoned

After surrender, most Confederate soldiers were pardoned and returned home, while leaders like Jefferson Davis faced short imprisonment. The South came under military occupation, Confederate money became worthless, and many former officers were barred from public office.

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.

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.

The SEC is a powerhouse conference with 16 teams and a rich Southern football tradition

Formed in 1933 after splitting from the Southern Conference, the Southeastern Conference began with 13 schools. It has since grown to 16 members, defining college football with numerous national championships and rabid regional rivalries.

Hundreds of women secretly joined the Union and Confederate armies during the war

Hear the story of women who disguised themselves as men to enlist in both Union and Confederate armies—serving as soldiers, medics, and spies.

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."

View animated battle maps from every major skirmish of the American Civil War.

The Confederate flag that most people recognize was not the national flag

The familiar Confederate flag was actually a battlefield banner; the Confederacy's true national flag, the "Stars and Bars," featured a blue canton with white stars and red-white-red stripes resembling the US flag.

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.

The nullification crisis tested whether states could defy federal law

In the 1830s, South Carolina declared federal tariffs void within its borders. President Andrew Jackson threatened military force, Congress passed a compromise tariff, and the episode ended with federal authority prevailing over state nullification.

The Emancipation Proclamation shifted the purpose of the war for the Union

Issued on Jan. 1, 1863, the Emancipation Proclamation declared enslaved people in Confederate-held territory free, redefining the Union's cause from merely preserving the nation to abolishing slavery.

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.

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.

The Articles of Confederation were not a federal system

Ratified in 1781, the Articles of Confederation left the states sovereign and independent, denied the national government power to tax or regulate commerce, and forced Congress to act through the states—exposing the limits of confederation and paving the way for US federalism.

Congress has formally declared war 11 times across five conflicts, the last in 1942

The five declared wars were the War of 1812, the Mexican-American War, the Spanish-American War, World War I, and World War II. Every major American military conflict since Korea, Vietnam, Iraq, and Afghanistan has been fought without a formal declaration.

The final shots of the Civil War were fired in the Arctic over 2 months after the South's surrender.

Rhode Island skipped the Constitutional Convention

Delegates from 12 of the original 13 states attended the 1787 Constitutional Convention. Rhode Island initially refused to participate, fearing centralized power. The state eventually joined the new republic after its ratification.

White supremacist groups like the Ku Klux Klan emerged to undermine Reconstruction

Founded in 1865 by former Confederate officers in Tennessee, the Ku Klux Klan used terror, murder, and intimidation to suppress Black political power and restore white Democratic control across the postwar South.

Lincoln's original reconstruction vision prioritized reconciliation

Proposed in 1863, Lincoln's Ten Percent Plan offered lenient readmission for Southern states once 10% of voters pledged loyalty and ended slavery. It was adopted in a few Union-occupied areas but was only partially implemented before his assassination in 1865.

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.

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.

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.

Southern states enacted voting restrictions aimed at circumventing Reconstruction

After 1877, former Confederate states passed poll taxes, literacy tests, property requirements, and grandfather clauses to disenfranchise Black voters—restrictions that remained in place for nearly a century until the Voting Rights Act of 1965.

The Missouri Compromise temporarily eased tensions over slavery's expansion

Passed in 1820, the Missouri Compromise admitted Missouri as a slave state and Maine as a free state—maintaining the fragile balance between proslavery and antislavery states in Congress. It also banned slavery north of latitude 36°30′.

The South built its wealth largely from slave labor

Before the Civil War, the Southern economy relied on roughly 4 million enslaved people producing cash crops such as cotton, rice, and sugarcane. Their forced labor generated immense profits—the South produced 75% of the world's cotton by 1860.

The Royal Governor of Virginia offered slaves their freedom if they escaped and fought for the British in the American Revolutionary War.

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.

Shays' rebellion pitted rebel veterans against the Revolution's leaders

The Revolutionary War led to independence and significant debt for most states. In 1786, a group of veterans and farmers from western Massachusetts protested against the state government’s increased taxes. Led by Daniel Shays, the group attempted to capture an armory in Springfield but failed.

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.

Twain served in a Confederate militia for two weeks

In 1861, a 25-year-old Twain joined the Marion Rangers, a pro-Confederate militia. The group disbanded after two weeks upon hearing that Ulysses S. Grant, General of the Union Army, was headed their way. Twain moved to Nevada, where he eventually took a job at a newspaper.

The end of Reconstruction paved the way for Jim Crow segregation

After federal troops withdrew in 1877, white Democrats regained control of Southern governments, dismantled Reconstruction reforms, and imposed segregation laws. By the 1890s, Jim Crow statutes had entrenched racial discrimination and Black disenfranchisement across the South.

'Presidential Reconstruction' attempted rapid reunification with minimal federal oversight

Led by Andrew Johnson after Lincoln's death, Presidential Reconstruction (1865-67) quickly restored Southern governments through mass pardons and lenient terms, allowing ex-Confederates to regain power and pass Black Codes that restricted freedpeople's rights.

The Articles of Confederation were the first governing documents of the United States

Drafted in 1777 and ratified in 1781, the articles created a weak national government without the ability to tax or regulate commerce. This led to problems for the new nation, necessitating the Constitutional Convention in 1787.

Radical Reconstruction began in response to the lenient policies of Andrew Johnson

In 1867, Congress passed the Reconstruction Acts—overriding Johnson's vetoes—placing the South under military rule and requiring new state constitutions, Black male suffrage, and ratification of the 14th Amendment before readmission.

Some historians claim that Mexico's victory at Puebla may have prevented France from arming the Confederacy

According to some experts, Napoleon III planned to ship weapons from Mexico to Confederate forces to break the Union naval blockade. The delay caused by the Battle of Puebla meant French resources didn't reach the Texas border until after the Union Army's decisive victory at Vicksburg.

The Dred Scott decision denied citizenship to people of African descent

In 1857, the Supreme Court ruled in Dred Scott v. Sandford that Black Americans could not be US citizens. The decision heightened an already brewing conflict and became a key factor in pushing the nation toward civil war.

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.

American annexation of Texas eventually sparked war with Mexico

After Texas won independence from Mexico in 1836, the US annexed it in 1845—despite Mexico’s refusal to recognize Texas as separate. That annexation, combined with a heated border dispute, triggered the Mexican-American War the following year.

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.

3 states did not officially ratify the Bill of Rights until 1939

Massachusetts, Connecticut, and Georgia originally rejected or tabled the amendments in 1791. With Virginia's ratification already clearing the three-fourths threshold of adoption, there was no legal pressure to revisit it—until all three states acted symbolically on the 150th anniversary of Congressional approval of the amendments.

Southern race riots in 1866 galvanized support for more radical Reconstruction

In 1866, white mobs in Memphis and New Orleans killed dozens of Black residents and burned Black neighborhoods. The massacres horrified Northerners, convincing Congress that stronger federal action was needed to protect freedpeople's rights and enforce Reconstruction.

The Revolution split the Iroquois Confederacy, as members allied with different sides.

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.

Southern Black Codes sought to preserve prewar racial labor structures

With little federal oversight, Southern states enacted laws effectively reestablishing slavery's economic and social order. These laws, known as the "Black Codes," restricted freed people's movement, labor, and property rights.