The American Civil War
The Union fought the Confederacy over slavery and secession.
About this topic
The American Civil War (1861 to 1865) was fought between the United States (the Union) and eleven Southern states that seceded to form the Confederate States of America. Its root cause was slavery: the Southern economy depended on enslaved labour for cotton, while the North was industrializing and increasingly opposed to slavery's expansion. Abraham Lincoln's election in 1860 triggered secession, and war began at Fort Sumter in April 1861.
The Union had more people, factories and railroads, and used a naval blockade. Key battles included Antietam, Gettysburg (July 1863), the turning point, and Vicksburg. Lincoln issued the Emancipation Proclamation in 1863 and the Gettysburg Address, defining the war as preserving a nation with equality. Generals Ulysses S. Grant and William T. Sherman, whose march to the sea used total war, wore down the Confederacy under Robert E. Lee. Lee surrendered at Appomattox in April 1865.
About 620,000 soldiers died, more than in any other American war. Lincoln was assassinated days later. Reconstruction brought the 13th, 14th and 15th Amendments, granting freedom, citizenship and voting rights to Black men, but ended in 1877 with Jim Crow laws taking hold. Misconception: states rights is often cited as the cause, but the right in question was slavery. The war tested whether a democracy could survive.
Key ideas
- 1861–1865
- Lincoln and Gettysburg
- 13th Amendment
Quick check
Use cases: where The American Civil War helps
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Studying the past helps explain today’s politics, borders, cultures and institutions.
Frequently asked questions
What is The American Civil War?
The Union fought the Confederacy over slavery and secession.
What will I learn in The American Civil War?
1861–1865. Lincoln and Gettysburg. 13th Amendment.
Is The American Civil War part of World History?
Yes. It is one of 80 World History topics on LearnViz HighSchoolEdu, with 3 key ideas, a live animation and a quick check.
Does the The American Civil War lab work on a phone or tablet?
Yes. The animation resizes to fit your screen and supports touch, so you can drag, tap and slide with your finger.
How should I study The American Civil War?
Read the summary and key ideas first, play with the interactive lab to see the idea in motion, then answer the quick check. If you get a question wrong, go back to the key idea it tests.
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