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US History Unit 5: Period 5: 1844–1877

Westward expansion reopened the question of slavery, leading to civil war, emancipation and the contested rebuilding of the nation.

Covers: Manifest destiny and the Mexican-American War, sectional conflict over slavery, the Civil War, emancipation, Reconstruction and its end

Study guide

Manifest destiny, the belief that Americans were meant to spread across the continent, drove expansion in the 1840s. The US annexed Texas (1845), divided Oregon with Britain, and won the Mexican-American War (1846–1848), gaining California and the Southwest in the Treaty of Guadalupe Hidalgo. The California Gold Rush drew settlers and immigrants. Each new territory raised the question of whether slavery would expand; the Wilmot Proviso proposed banning it in lands from Mexico.

Compromises failed one after another. The Compromise of 1850 admitted California as free but strengthened the Fugitive Slave Act, angering Northerners; Harriet Beecher Stowe's Uncle Tom's Cabin turned many against slavery. The Kansas-Nebraska Act (1854) used popular sovereignty, leading to violence in "Bleeding Kansas" and the creation of the antislavery Republican Party. The Dred Scott decision (1857) ruled that Black people weren't citizens and Congress couldn't ban slavery in territories. John Brown's raid (1859) deepened Southern fears, and after Abraham Lincoln's election in 1860, Southern states seceded.

The Civil War (1861–1865) began at Fort Sumter. The North had more people, factories and railroads; the South had skilled generals and fought defensively. The Emancipation Proclamation (1863) made ending slavery a war aim and allowed Black men to serve in the Union army. Gettysburg and Vicksburg (1863) turned the tide, and Lee surrendered at Appomattox in 1865, days before Lincoln's assassination. Reconstruction brought the 13th (abolished slavery), 14th (citizenship and equal protection) and 15th (Black male suffrage) Amendments, the Freedmen's Bureau and Black officeholders. Southern resistance through Black Codes, the Ku Klux Klan and sharecropping limited freedom, and the Compromise of 1877 withdrew federal troops and ended Reconstruction.

Lincoln first fought to preserve the Union, not to end slavery, partly to keep slaveholding border states like Kentucky and Maryland loyal. The Emancipation Proclamation was a war measure that freed enslaved people only in areas in rebellion. The Republican Party was built on a 'free labor' ideology that saw slavery as a threat to the opportunities of independent white farmers and workers. In the 1858 Lincoln–Douglas debates, Lincoln opposed slavery's spread, while Stephen Douglas defended popular sovereignty.

Heavy Irish and German Catholic immigration sparked nativism. The anti-immigrant Know-Nothing (American) Party briefly won major elections in the mid-1850s as the Whig Party collapsed. During the war, the Union government passed the Homestead Act and Pacific Railway Act (1862) and created a national banking system, an income tax and a draft. The draft sparked the 1863 New York City draft riots, and Lincoln suspended habeas corpus. The Confederacy also drafted soldiers and suffered inflation and shortages.

Lincoln and then Andrew Johnson favored lenient terms for the South. Radical Republicans in Congress passed the Reconstruction Acts (1867), which put the South under military rule and required Black male suffrage, and they impeached Johnson, who was acquitted. After the Panic of 1873, Northern fatigue and white Southern violence eroded support for Reconstruction.

Key ideas

• Manifest destiny drove expansion and reopened the slavery question.
• Each compromise over slavery's expansion broke down.
• Lincoln's election triggered secession.
• The Emancipation Proclamation changed the war's purpose.
• Reconstruction amendments promised equality, but white resistance and the Compromise of 1877 limited it.

Formulas and rules

Common mistakes

• Thinking the Emancipation Proclamation freed all enslaved people immediately; it applied to Confederate-held areas.
• Forgetting that the 15th Amendment covered men only.

Words to know

Manifest destiny

The belief that the US was destined to expand across the continent.

Mexican-American War

1846–1848 war in which the US gained California and the Southwest.

Treaty of Guadalupe Hidalgo

The 1848 treaty ending the Mexican-American War.

Wilmot Proviso

A failed proposal to ban slavery in land taken from Mexico.

Compromise of 1850

Admitted California as free and passed a stronger Fugitive Slave Act.

Fugitive Slave Act

Required Northerners to help return people who escaped slavery.

Popular sovereignty

Letting settlers in a territory vote on slavery.

Kansas-Nebraska Act

The 1854 law using popular sovereignty; led to Bleeding Kansas.

Republican Party

Founded in the 1850s to stop slavery's expansion.

Dred Scott v. Sandford

The 1857 ruling that Black people weren't citizens and Congress couldn't ban slavery in territories.

Secession

Southern states leaving the Union after Lincoln's 1860 election.

Emancipation Proclamation

Lincoln's 1863 order freeing enslaved people in Confederate areas.

13th Amendment

Abolished slavery (1865).

14th Amendment

Granted citizenship and equal protection of the laws (1868).

15th Amendment

Barred denying the vote based on race (1870).

Black Codes

Southern laws restricting freedpeople's rights after the war.

Sharecropping

Farming land for a share of the crop, which often trapped families in debt.

Compromise of 1877

Ended Reconstruction by withdrawing federal troops from the South.

Sample practice questions

5 more questions like these, from level 1 to 5, are in the practice set.