AP U.S. History Unit 5

Definition: Manifest Destiny was the belief that American expansion across the continent to the Pacific Ocean was inevitable, justified, and divinely ordained.

Coined: 1845 by journalist John L. O'Sullivan who wrote of America's "manifest destiny to overspread the continent"

Justifications:

• Divine Blessing: God ordained American expansion
• Racial Superiority: Anglo-Saxon race destined to dominate "inferior" peoples
• Democratic Mission: Spread democracy and republican institutions
• Economic Opportunity: Access to resources, trade routes, farmland
• Security: Prevent European powers from controlling North America

Reality: Manifest Destiny masked conquest, Native American displacement, and racial oppression with lofty rhetoric

Texas Annexation (1845)

Background:

• Texas won independence from Mexico (1836) at Battle of San Jacinto
• Requested U.S. annexation but Jackson, Van Buren delayed (feared war with Mexico, slavery controversy)

1844 Election: James K. Polk (Democrat) ran on expansionist platform; defeated Henry Clay

Annexation: Outgoing President John Tyler pushed through joint resolution (simple majority) rather than treaty (2/3 Senate); Texas admitted as slave state

Consequences: Mexico broke diplomatic relations; set stage for Mexican-American War

Oregon Territory (1846)

Background: U.S. and Britain jointly occupied Oregon Territory (Pacific Northwest)

Campaign Slogan: "Fifty-four Forty or Fight!"—demanded entire territory to 54°40' latitude

Oregon Treaty (1846): Compromise at 49th parallel (current Canadian border)

Significance: Peaceful resolution; secured Pacific Northwest; avoided war with Britain

Continued Displacement: Western expansion dispossessed Native tribes of ancestral lands

Broken Treaties: U.S. repeatedly violated agreements with Native nations

Violence: Military campaigns forced tribes onto reservations

Cultural Destruction: Federal policies aimed to assimilate and "civilize" Native peoples

• Texas Annexation: Mexico never recognized Texas independence; viewed annexation as act of war
• Border Dispute: Texas claimed Rio Grande as border; Mexico insisted on Nueces River (further north)
• Unpaid Debts: Mexico owed money to American citizens; refused to pay
• Polk's Expansionism: President Polk wanted California and Southwest; sent John Slidell to buy territories; Mexico refused
• Provocation: Polk ordered General Zachary Taylor to disputed territory between rivers; Mexican forces attacked

Declaration: Polk claimed "American blood has been shed on American soil"; Congress declared war

Opposition:

• Whigs: Saw war as Democratic land grab for slavery expansion
• Abraham Lincoln: Challenged Polk's justification with "Spot Resolutions"—demanded to know exact spot where blood was shed
• Henry David Thoreau: Refused to pay taxes; wrote "Civil Disobedience" opposing war
• Abolitionists: Denounced war as pro-slavery conspiracy

Major Campaigns:

• Northern Mexico: Zachary Taylor won battles at Monterrey, Buena Vista
• California: U.S. forces captured California with little resistance; Bear Flag Revolt
• Mexico City: General Winfield Scott landed at Veracruz, marched inland, captured capital (1847)

Terms:

• Mexican Cession: Mexico ceded ~525,000 square miles (California, Nevada, Utah, most of Arizona, New Mexico, parts of Colorado, Wyoming)
• Rio Grande Border: Established as Texas-Mexico boundary
• Payment: U.S. paid Mexico $15 million
• Debt Assumption: U.S. assumed $3.25 million in Mexican debts to Americans
• Citizenship: Mexican residents in ceded territory could become U.S. citizens

Significance: Added ~1/3 of Mexico's territory to U.S.; fulfilled Manifest Destiny; reignited sectional crisis over slavery in new territories

Proposal: Representative David Wilmot (Pennsylvania Democrat) proposed banning slavery in any territory acquired from Mexico

Argument: New lands should be reserved for free white labor, not slavery

Debate:

• North: Supported Wilmot Proviso; opposed slavery expansion
• South: Furious; claimed right to bring property (enslaved people) into territories

Outcome: Passed House multiple times; defeated in Senate

Significance: Revealed sectional divisions were geographic, not party-based; North vs. South rather than Democrat vs. Whig; foreshadowed collapse of national parties

Gold Rush (1849): California's population exploded; applied for statehood

Problem: California sought admission as free state; would upset balance (15 free, 15 slave states)

Southern Threat: Some Southern leaders threatened secession if California admitted as free state

Need: Compromise to preserve Union

Architect: Henry Clay ("Great Compromiser") crafted package deal

Support: Senator Daniel Webster supported compromise despite Northern opposition; Senator Stephen Douglas steered passage

Opposition: Senator John C. Calhoun (South Carolina) opposed; demanded stronger protection for slavery

Five-Part Package:

1. California Admitted as Free State

• North Won: Broke sectional balance; 16 free vs. 15 slave states

2. Popular Sovereignty in Utah and New Mexico Territories

• Concept: Settlers would vote on slavery (bypassed federal decision)
• Problem: Vague; unclear when vote would occur

3. Texas-New Mexico Border Settled

• Texas gave up land claims to New Mexico; U.S. assumed $10 million Texas debt

4. Slave Trade Abolished in Washington, D.C.

• Symbolic Victory: Ended slave auctions in nation's capital
• Limitation: Didn't end slavery itself in D.C.; only the trade

5. Fugitive Slave Act of 1850 — MOST CONTROVERSIAL

• Provisions:
• Federal commissioners appointed to pursue fugitive enslaved people
• Accused had no jury trial; couldn't testify on own behalf
• Citizens required to assist in capturing runaways; $1,000 fine for helping fugitives
• Commissioners paid $10 if fugitive returned to slavery, $5 if freed (incentive to enslave)
• Northern Response: Outrage; "slave catchers" hunted people in free states; some free Blacks kidnapped
• Resistance: Underground Railroad intensified; personal liberty laws passed; violent rescues of captured people
• Impact: Radicalized many Northerners; made slavery a Northern problem, not just Southern

Temporary Relief: Compromise delayed crisis; gave Union 10 more years

Deeper Divisions: Fugitive Slave Act inflamed North; South still felt threatened

Last National Compromise: Future attempts at compromise would fail

Economic Differences

North: Industrial, urban, diverse economy; wage labor; immigrants

South: Agricultural, rural, cotton-dominated; enslaved labor; plantation system

Conflict: Tariffs (North wanted protection; South wanted free trade), internal improvements, national bank

Uncle Tom's Cabin (1852)

Author: Harriet Beecher Stowe

Content: Novel depicting horrors of slavery; emotional, sympathetic portrayal of enslaved people

Impact: Bestseller; converted thousands to abolitionism; South denounced it as lies

Lincoln's Quote: Allegedly called Stowe "the little woman who wrote the book that started this great war"

Kansas-Nebraska Act (1854)

Proposed By: Senator Stephen Douglas

Provision: Created Kansas and Nebraska territories; allowed popular sovereignty (let settlers vote on slavery)

Impact: Repealed Missouri Compromise’s 36°30' line; led to violent conflict (“Bleeding Kansas”)

Northern Reaction: Outrage; seen as pro-slavery plot

Significance: Destroyed Whig Party; gave rise to Republican Party (anti-slavery expansion)

Bleeding Kansas

What: Violent clashes between pro-slavery and anti-slavery settlers in Kansas

Key Event: Sack of Lawrence (pro-slavery attack on town); Pottawatomie Massacre (John Brown's anti-slavery attack)

Significance: Showed popular sovereignty would not resolve slavery peacefully

Foreshadowed: The violence of the coming Civil War

Dred Scott v. Sandford (1857)

Chief Justice: Roger B. Taney

Decision: Enslaved people cannot be citizens and cannot sue; Congress cannot ban slavery in territories

Effect: Declared Missouri Compromise unconstitutional; made slavery expansion possible anywhere

Northern Reaction: Outrage; strengthened Republican opposition to "slave power"

Other Sectional Flashpoints

• Caning of Charles Sumner (1856): Congressman Preston Brooks beat anti-slavery Senator Charles Sumner in the Senate—symbol of breakdown in civil discourse.
• John Brown’s Raid (1859): Tried to spark slave uprising at Harpers Ferry, VA; failed but inflamed South.

• Split Parties: Democrats split (Northern—Stephen Douglas; Southern—John C. Breckinridge); Republicans—Abraham Lincoln; Constitutional Union Party—John Bell
• Lincoln's Platform: Stop slavery expansion (NOT abolition); Homestead Act, protective tariffs, transcontinental railroad
• Result: Lincoln won all free states, no slave states; won with only ~40% popular vote
• Southern Reaction: Saw Lincoln as existential threat to slavery; within months, SC and then 10 other states seceded

• South Carolina: First to secede (Dec. 1860); followed by 10 others
• Confederate States of America: Formed under President Jefferson Davis; constitution protected slavery
• Crittenden Compromise: Failed last-ditch effort to preserve Union by protecting slavery; rejected

• Fort Sumter: April 1861; first shots of war in Charleston Harbor; Confederacy attacked Union fort
• First Bull Run (Manassas): July 1861; Confederate victory shocked North
• Antietam: Sept. 1862; Union victory; bloodiest single day; led to Emancipation Proclamation
• Gettysburg: July 1863; Union victory in Pennsylvania; South never invaded North again—TURNING POINT
• Vicksburg: July 1863; Union gained control of Mississippi River; split Confederacy
• Sherman's March: 1864; "total war" devastation of South; broke Southern will to fight
• Appomattox: April 1865; Lee surrendered to Grant; war ended

Union Advantages

• Greater population, industry, railroads
• Naval superiority
• Political leadership (Lincoln)

Confederacy Advantages

• Home-field advantage
• Military leadership (Lee, Jackson)
• Defensive war

• Suspended habeas corpus to jail dissenters without trial
• Issued Emancipation Proclamation (1863) freeing slaves in rebelling states
• Increased federal power, income taxes, national bank, greenbacks (paper money)

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