The role of slavery in the leadup to the Civil War

Causes

1. Expansion of Slavery into New Territories — Heavyweight

• As the US grew westward  the big question was whether new states would allow slavery. This issue directly caused secession

2.  Cotton Gin & Southern Economy — Heavyweight

   • Invented in 1793, the cotton gin increased the demand for slavery. The south depended on it.

3. Abolitionist Movement & Northern Resistance — Midweight

   • Abolitionists increased tension with powerful books, speeches and action. ex: Frederick Douglass’ speech

4. Political Failures and Compromises — Midweight

   • Compromises tried to balance free/slave state power but only delayed conflict (Compromise of 1850, Fugitive Slave Act). Increased Northern frustration, confirmed Southern dominance in national policy.

5. Lincoln’s Election in 1860 — Trigger

   • Lincoln wasn’t an abolitionist but opposed slavery’s expansion. Southern states saw this as a direct threat and seceded after his win. Not the root cause — but the final straw that made war inevitable.

Effects

 1. Secession of Southern States — Heavyweight

• Starting with South Carolina, 11 states seceded because they feared slavery would be abolished.

2. Outbreak of the Civil War — Heavyweight

   • The Fort Sumter attack followed secession, beginning the war.

3.  Radicalization of Northern Politics - Midweight

   • Abolitionists and Radical Republicans pushed Lincoln and the Union to turn the war into a fight against slavery.

   • Led to major wartime policy shifts like the Emancipation Proclamation.

   • Slavery turned the war from just “preserving the Union” to a moral cause.

4. Deepened Racial and Regional Tensions — Lifelong Effect

   • Even after the war ended, the legacy of slavery remained — in segregation, economic inequality, and continued racial injustice.

   • Still shapes society today

Missouri Compromise (1820)

Drew a line dividing free and slave territories to resolve the issue of slavery in the louisiana purchase bc it needed to address the expansion of slavery into new states. So, missouri was admited as a slave state and maine was admitted as a free state. This maintained balance in congress. However, it also prohibited slavery in the remainding portion of the louisiana purchase, north of the line.

Compromise of 1850

North gets:

• california

• slave trade prohibited in washington

• texas loses boundary dispute w/ new mexico

South gets:

• no slavery restrictions in utah or NM

• slave holding is permited in washington

• texas gets 10M dollars

• The fugitive slave act is strengthened because northerners have to return escaped slaves

Kansas-Nebraska Act (1854)

• let states vote on slavery, which led to violence in places like “Bleeding Kansas.”

First Battle of Bull Run

The first land engagement of the Civil War, which took place on July 21st, 1861, at Manassas Junction, Virginia, and at which Union troops quickly retreated.

Second Battle of Bull Run

Civil War engagement that took place one year after the first Battle of Bull Run, on August 29-30, during which Confederates captured the federal supply depot at Manassas Junction, Virginia, and forced Union troops back to Washington.

Battle of Antietam

One of the bloodiest battles of the Civil War, fought to a standoff on September 17, 1862, in western Maryland.

The contrabands

Slaves who sought refuge in Union military camps or who lived in areas of the Confederacy under Union control.

Radical Republicans

Group within the Republican Party in the 1850s and 1860s that advocated strong resistance to the expansion of slavery, opposition to compromise with the South in the secession crisis of 1860-1861, emancipation and arming of Black soldiers during the Civil War, and equal civil and political rights for Blacks during Reconstruction.

Emancipation Proclamation

Declaration issued by President Abraham Lincoln; the preliminary proclamation on September 22, 1862, freed the slaves in areas under Confederate control as of January 1, 1863, the date of the final proclamation, which also authorized the enrollment of Black soldiers into the Union army.

Second American Revolution

The transformation of American government and society brought about by the Civil War.

Ex Parte Milligan

1866 Supreme Court case that declared it unconstitutional to bring accused persons before military tribunals where civil courts were available.

Homestead Act

1862 law that authorized Congress to grant 160 acres of public land to a western settler, who had to live on the land for five years to establish title.

Transcontinental railroad

First line across the continent from Omaha, Nebraska, to Sacramento, California, established in 1869 with the linkage of the Union Pacific and Central Pacific railroads at Promontory, Utah.

Navajos Long Walk

The forced removal of 8,000 Navajos from their lands by Union forces to a reservation in the 1860s.

Sanitary Fairs

Fund-raising bazaars led by women on behalf of Civil War soldiers; the fairs offered items such as uniforms and banners, as well as other emblems of war.

King Cotton Diplomacy

An attempt during the Civil War by the South to encourage British intervention by banning cotton exports.

Battle of Gettysburg

Battle fought in southern Pennsylvania, July 1-3, 1863; the Confederate defeat and the simultaneous loss at Vicksburg marked the military turning point of the Civil War.

Battle of Vicksburg

The fall of Vicksburg, Mississippi, to General Ulysses S. Grant's army on July 4, 1863, after two months of siege; a turning point in the war because it gave the Union control of the Mississippi River.

Sea Islands Experiment

The 1861 pre-Reconstruction social experiment that involved converting slave plantations into places where former slaves could work for wages or own land. Former slaves also received education and access to improved shelter and food.

Ten-Percent Plan of Reconstruction

President Lincoln's proposal for reconstruction, issued in 1863, in which southern states would rejoin the Union if 10 percent of the 1860 electorate signed loyalty pledges, accepted emancipation, and had received presidential pardons.

Wade-Davis Bill

Radical Republicans' 1864 plan for reconstruction that required loyalty oaths, abolition of slavery, repudiation of war debts, and denial of political rights to high-ranking Confederate officials; President Lincoln refused to sign the bill.

Thirteenth Amendment

Constitutional amendment adopted in 1865 that irrevocably abolished slavery throughout the United States.

Appomattox Courthouse, Virginia

Site of the surrender of Confederate general Robert E. Lee to Union general Ulysses S. Grant on April 9, 1865, marking the end of the Civil War.