Manifest Destiny and Expansion

Syllabus

5.1 Contextualizing Period 5

Learning Objective	Preview: Unit 5 Key Concepts
Unit 5.A Explain the context in which sectional conflict emerged from 1844 to 1877.	KC-5.1 The United States became more connected with the world, pursued an expansionist foreign policy in the Western Hemisphere, and emerged as the destination for many migrants from other countries. KC-5.1.I Popular enthusiasm for U.S. expansion, bolstered by economic and security interests, resulted in the acquisition of new territories, substantial migration westward, and new overseas initiatives. KC-5.1.II In the 1840s and 1850s, Americans continued to debate questions about rights and citizenship for various groups of U.S. inhabitants. KC-5.2 Intensified by expansion and deepening regional divisions, debates over slavery and other economic, cultural, and political issues led the nation into civil war. KC-5.2.I Ideological and economic differences over slavery produced an array of diverging responses from Americans in the North and the South. KC-5.2.II Debates over slavery came to dominate political discussion in the 1850s, culminating in the bitter election of 1860 and the secession of Southern states. KC-5.3 The Union victory in the Civil War and the contested reconstruction of the South settled the issues of slavery and secession, but left unresolved many questions about the power of the federal government and citizenship rights. KC-5.3.I The North’s greater manpower and industrial resources, the leadership of Abraham Lincoln and others, and the decision to emancipate enslaved people eventually led to the Union military victory over the Confederacy in the devastating Civil War. KC-5.3.II.i Reconstruction and the Civil War ended slavery, altered relationships between the states and the federal government, and led to debates over new definitions of citizenship, particularly regarding the rights of African Americans, women, and other minorities.

Learning Objective

Preview: Unit 5 Key Concepts

Unit 5.A
Explain the context in which sectional conflict emerged from 1844 to 1877.

KC-5.1 The United States became more connected with the world, pursued an expansionist foreign policy in the Western Hemisphere, and emerged as the destination for many migrants from other countries.
- KC-5.1.I Popular enthusiasm for U.S. expansion, bolstered by economic and security interests, resulted in the acquisition of new territories, substantial migration westward, and new overseas initiatives.
- KC-5.1.II In the 1840s and 1850s, Americans continued to debate questions about rights and citizenship for various groups of U.S. inhabitants.
KC-5.2 Intensified by expansion and deepening regional divisions, debates over slavery and other economic, cultural, and political issues led the nation into civil war.
- KC-5.2.I Ideological and economic differences over slavery produced an array of diverging responses from Americans in the North and the South.
- KC-5.2.II Debates over slavery came to dominate political discussion in the 1850s, culminating in the bitter election of 1860 and the secession of Southern states.
KC-5.3 The Union victory in the Civil War and the contested reconstruction of the South settled the issues of slavery and secession, but left unresolved many questions about the power of the federal government and citizenship rights.
- KC-5.3.I The North’s greater manpower and industrial resources, the leadership of Abraham Lincoln and others, and the decision to emancipate enslaved people eventually led to the Union military victory over the Confederacy in the devastating Civil War.
- KC-5.3.II.i Reconstruction and the Civil War ended slavery, altered relationships between the states and the federal government, and led to debates over new definitions of citizenship, particularly regarding the rights of African Americans, women, and other minorities.

5.2 Manifest Destiny

Thematic Focus	Learning Objective	Historical Developments
GEO Geography and the Environment — Geographic and environmental factors, including competition over and debates about natural resources, shape the development of America and foster regional diversity. The development of America impacts the environment and reshapes geography, which leads to debates about environmental and geographic issues.	Unit 5.B Explain the causes and effects of westward expansion from 1844 to 1877.	KC-5.1.I.A The desire for access to natural and mineral resources and the hope of many settlers for economic opportunities or religious refuge led to an increased migration to and settlement in the West. KC-5.1.I.B Advocates of annexing western lands argued that Manifest Destiny and the superiority of American institutions compelled the United States to expand its borders westward to the Pacific Ocean; however, this frequently provoked competition and violent conflict. KC-5.1.I.D Westward migration was boosted during and after the Civil War by the passage of new legislation promoting western transportation and economic development. KC-5.1.I.E U.S. interest in expanding trade led to economic, diplomatic, and cultural initiatives to create more ties with Asia.

5.3 The Mexican–American War

Thematic Focus	Learning Objective	Historical Developments
WOR America in the World — Diplomatic, economic, cultural, and military interactions between empires, nations, and peoples shape the development of America and America’s increasingly important role in the world.	Unit 5.C Explain the causes and effects of the Mexican– American War.	KC-5.1.I.C The United States added large territories in the West through victory in the Mexican– American War and diplomatic negotiations, raising questions about the status of slavery, American Indians, and Mexicans in the newly acquired lands. KC-5.1.II.C U.S. government interaction and conflict with Mexican Americans and American Indians increased in regions newly taken from American Indians and Mexico, altering these groups’ economic self-sufficiency and cultures.

Source: College Board AP Course and Exam Description

Period 5 runs from 1844 to 1877. It is the period in which the argument over slavery stops being political and becomes military.

Expansion is the trigger. The desire for access to natural and mineral resources 自然与矿产资源, and the hope of settlers for land, pushed Americans west. Advocates justified annexation through Manifest Destiny 天定命运论 - the claim that the United States was destined, and superior enough, to spread across the continent.

The Mexican-American War 美墨战争 added enormous territory in the West. Later, wartime legislation such as the Homestead Act 宅地法 boosted migration further, and interest in expanding trade produced economic and diplomatic initiatives abroad.

Expansion also meant conflict. The government's interaction with Mexican Americans 墨西哥裔美国人 and American Indians produced dispossession, resistance, and new legal disputes over land and citizenship.

Vocabulary Train

English	Chinese	Pinyin
natural and mineral resources	自然与矿产资源	zì rán yǔ kuàng chǎn zī yuán
Manifest Destiny	天定命运论	tiān dìng mìng yùn lùn
Mexican-American War	美墨战争	měi mò zhàn zhēng
Homestead Act	宅地法	zhái dì fǎ
Mexican Americans	墨西哥裔美国人	mò xī gē yì měi guó rén

5.4 5.5 5.6

Why Expansion Broke the Political System

Syllabus

5.4 The Compromise of 1850

Thematic Focus	Learning Objective	Historical Developments
NAT American and National Identity — The development of and debates about democracy, freedom, citizenship, diversity, and individualism shape American national identity, cultural values, and beliefs about American exceptionalism, and in turn, these ideas shape political institutions and society. Throughout American history, notions of national identity and culture have coexisted with varying degrees of regional and group identities.	Unit 5.D Explain the similarities and differences in how regional attitudes affected federal policy in the period after the Mexican–American War.	KC-5.2.II.A The Mexican Cession led to heated controversies over whether to allow slavery in the newly acquired territories. KC-5.2.II.B.i The courts and national leaders made a variety of attempts to resolve the issue of slavery in the territories, including the Compromise of 1850.

5.5 Sectional Conflict: Regional Differences

Thematic Focus	Learning Objective	Historical Developments
SOC Social Structures — Social categories, roles, and practices are created, maintained, challenged, and transformed throughout American history, shaping government policy, economic systems, culture, and the lives of citizens.	Unit 5.E Explain the effects of immigration from various parts of the world on American culture from 1844 to 1877.	KC-5.1.II.A Substantial numbers of international migrants continued to arrive in the United States from Europe and Asia, mainly from Ireland and Germany, often settling in ethnic communities where they could preserve elements of their languages and customs. KC-5.1.II.B A strongly anti-Catholic nativist movement arose that was aimed at limiting new immigrants’ political power and cultural influence.
	Unit 5.F Explain how regional differences related to slavery caused tension in the years leading up to the Civil War.	KC-5.2.I.A The North’s expanding manufacturing economy relied on free labor in contrast to the Southern economy’s dependence on enslaved labor. Some Northerners did not object to slavery on principle but claimed that slavery would undermine the free labor market. As a result, a free-soil movement arose that portrayed the expansion of slavery as incompatible with free labor. KC-5.2.I.B African American and white abolitionists, although a minority in the North, mounted a highly visible campaign against slavery, presenting moral arguments against the institution, assisting escapes, and sometimes expressing a willingness to use violence to achieve their goals. KC-5.2.I.C Defenders of slavery based their arguments on racial doctrines, the view that slavery was a positive social good, and the belief that slavery and states’ rights were protected by the Constitution.

5.6 Failure of Compromise

Thematic Focus	Learning Objective	Historical Developments
PCE Politics and Power — Debates fostered by social and political groups about the role of government in American social, political, and economic life shape government policy, institutions, political parties, and the rights of citizens.	Unit 5.G Explain the political causes of the Civil War.	KC-5.2.II.B.ii The courts and national leaders made a variety of attempts to resolve the issue of slavery in the territories, including the Kansas–Nebraska Act, and the Dred Scott decision, but these ultimately failed to reduce conflict. KC-5.2.II.C The Second Party System ended when the issues of slavery and anti-immigrant nativism weakened loyalties to the two major parties and fostered the emergence of sectional parties, most notably the Republican Party in the North.

Source: College Board AP Course and Exam Description

Each attempted compromise settles slavery in new territory, then breaks - and each failure narrows the room for the next — Each compromise dealt with slavery in the territories, and each collapse left less room for the next one

Acquiring land forced a question that could not be avoided: would slavery expand into the new territories? Every attempt to answer it produced a temporary settlement that then failed.

The Compromise of 1850 1850年妥协案 admitted California as free and included a strict Fugitive Slave Act 逃奴法, which enraged the North by requiring its citizens to participate in enforcement.
Popular sovereignty 人民主权原则 - letting territorial settlers decide - produced violence in Kansas rather than a settlement.
The Dred Scott decision 德雷德·斯科特案 held that Congress could not ban slavery in the territories, removing compromise as a legal option.

Ideological and economic differences produced diverging responses 分歧的回应 to slavery, from abolitionism to proslavery arguments defending it as a positive good. By the 1850s slavery dominated political discussion, destroying the existing party system and producing the new Republican Party 共和党.

Vocabulary Train

English	Chinese	Pinyin
Compromise of 1850	1850年妥协案	1850 nián tuǒ xié àn
Fugitive Slave Act	逃奴法	táo nú fǎ
Popular sovereignty	人民主权原则	rén mín zhǔ quán yuán zé
Dred Scott decision	德雷德·斯科特案	dé léi dé · sī kē tè àn
diverging responses	分歧的回应	fēn qí de huí yìng
Republican Party	共和党	gòng hé dǎng

5.7 5.8 5.9

Secession and the Civil War

Syllabus

5.7 Election of 1860 and Secession

Thematic Focus	Learning Objective	Historical Developments
PCE Politics and Power — Debates fostered by social and political groups about the role of government in American social, political, and economic life shape government policy, institutions, political parties, and the rights of citizens.	Unit 5.H Describe the effects of Lincoln’s election.	KC-5.2.II.D Abraham Lincoln’s victory on the Republicans’ free-soil platform in the presidential election of 1860 was accomplished without any Southern electoral votes. After a series of contested debates about secession, most slave states voted to secede from the Union, precipitating the Civil War.

5.8 Military Conflict in the Civil War

Thematic Focus	Learning Objective	Historical Developments
WOR America in the World — Diplomatic, economic, cultural, and military interactions between empires, nations, and peoples shape the development of America and America’s increasingly important role in the world.	Unit 5.I Explain the various factors that contributed to the Union victory in the Civil War.	KC-5.3.I.A Both the Union and the Confederacy mobilized their economies and societies to wage the war even while facing considerable home front opposition. KC-5.3.I.D Although the Confederacy showed military initiative and daring early in the war, the Union ultimately succeeded due to improvements in leadership and strategy, key victories, greater resources, and the wartime destruction of the South’s infrastructure.

5.9 Government Policies During the Civil War

Thematic Focus	Learning Objective	Historical Developments
NAT American and National Identity — The development of and debates about democracy, freedom, citizenship, diversity, and individualism shape American national identity, cultural values, and beliefs about American exceptionalism, and in turn, these ideas shape political institutions and society. Throughout American history, notions of national identity and culture have coexisted with varying degrees of regional and group identities.	Unit 5.J Explain how Lincoln’s leadership during the Civil War impacted American ideals over the course of the war.	KC-5.3.I.B Lincoln and most Union supporters began the Civil War to preserve the Union, but Lincoln’s decision to issue the Emancipation Proclamation reframed the purpose of the war and helped prevent the Confederacy from gaining full diplomatic support from European powers. Many African Americans fled southern plantations and enlisted in the Union Army, helping to undermine the Confederacy. KC-5.3.I.C Lincoln sought to reunify the country and used speeches such as the Gettysburg Address to portray the struggle against slavery as the fulfillment of America’s founding democratic ideals.

Source: College Board AP Course and Exam Description

The election of 1860 1860年大选 brought Abraham Lincoln 林肯 to power on a platform of preventing slavery's expansion. Southern states responded by seceding 脱离联邦, and the war followed.

The Union won because of greater manpower and industrial resources 更多的人力与工业资源, Lincoln's leadership, and, decisively, the Emancipation Proclamation 解放黑奴宣言, which turned the war into a war against slavery and enabled the enlistment of African American soldiers.

Government policy changed on both sides during the war: conscription, taxation, and an expanded federal role in the economy. African Americans' service and the actions of enslaved people who freed themselves by reaching Union lines shaped the outcome as well.

Vocabulary Train

English	Chinese	Pinyin
election of 1860	1860年大选	1860 nián dà xuǎn
Abraham Lincoln	林肯	lín kěn
seceding	脱离联邦	tuō lí lián bāng
greater manpower and industrial resources	更多的人力与工业资源	gèng duō de rén lì yǔ gōng yè zī yuán
Emancipation Proclamation	解放黑奴宣言	jiě fàng hēi nú xuān yán

5.10

Reconstruction

Syllabus

5.10 Reconstruction

Thematic Focus	Learning Objective	Historical Developments
PCE Politics and Power — Debates fostered by social and political groups about the role of government in American social, political, and economic life shape government policy, institutions, political parties, and the rights of citizens.	Unit 5.K Explain the effects of government policy during Reconstruction on society from 1865 to 1877.	KC-5.3.II.ii Reconstruction altered relationships between the states and the federal government and led to debates over new definitions of citizenship, particularly regarding the rights of African Americans, women, and other minorities. KC-5.3.II.A The 13th Amendment abolished slavery, while the 14th and 15th amendments granted African Americans citizenship, equal protection under the laws, and voting rights. KC-5.3.II.B The women’s rights movement was both emboldened and divided over the 14th and 15th amendments to the Constitution. KC-5.3.II.C Efforts by radical and moderate Republicans to change the balance of power between Congress and the presidency and to reorder race relations in the defeated South yielded some short-term successes. Reconstruction opened up political opportunities and other leadership roles to formerly enslaved persons but it ultimately failed, due both to determined Southern resistance and the North’s waning resolve.

Source: College Board AP Course and Exam Description

Reconstruction 重建时期 attempted to settle three questions: the status of the freedpeople, the terms of readmission for the southern states, and the balance of power between the states and the federal government.

The constitutional achievement is the Reconstruction Amendments 重建修正案:

The 13th Amendment 第十三修正案 abolished slavery.
The 14th Amendment 第十四修正案 granted citizenship and equal protection.
The 15th Amendment 第十五修正案 prohibited denial of the vote on grounds of race.

The women's rights movement was both emboldened and divided 既受鼓舞又出现分裂 by the 14th and 15th Amendments, because they extended rights on the basis of race while introducing the word "male" into the Constitution.

Radical and moderate Republicans 激进派与温和派共和党人 worked to change the balance of power between Congress and the presidency and to reshape southern society, through the Freedmen's Bureau, military occupation, and new state constitutions.

Vocabulary Train

English	Chinese	Pinyin
Reconstruction	重建时期	chóng jiàn shí qī
Reconstruction Amendments	重建修正案	chóng jiàn xiū zhèng àn
13th Amendment	第十三修正案	dì shí sān xiū zhèng àn
14th Amendment	第十四修正案	dì shí sì xiū zhèng àn
15th Amendment	第十五修正案	dì shí wǔ xiū zhèng àn
emboldened and divided	既受鼓舞又出现分裂	jì shòu gǔ wǔ yòu chū xiàn fēn liè
Radical and moderate Republicans	激进派与温和派共和党人	jī jìn pài yǔ wēn hé pài gòng hé dǎng rén

5.11

The Failure of Reconstruction

Syllabus

5.11 Failure of Reconstruction

Thematic Focus	Learning Objective	Historical Developments
NAT American and National Identity — The development of and debates about democracy, freedom, citizenship, diversity, and individualism shape American national identity, cultural values, and beliefs about American exceptionalism, and in turn, these ideas shape political institutions and society. Throughout American history, notions of national identity and culture have coexisted with varying degrees of regional and group identities.	Unit 5.L Explain how and why Reconstruction resulted in continuity and change in regional and national understandings of what it meant to be American.	KC-5.3.II.D Southern plantation owners continued to own the majority of the region’s land even after Reconstruction. Formerly enslaved persons sought land ownership but generally fell short of self-sufficiency, as an exploitative and soil-intensive sharecropping system limited blacks’ and poor whites’ access to land in the South. KC-5.3.II.E Segregation, violence, Supreme Court decisions, and local political tactics progressively stripped away African American rights, but the 14th and 15th amendments eventually became the basis for court decisions upholding civil rights in the 20th century.

Source: College Board AP Course and Exam Description

Reconstruction's gains were reversed, and the exam expects the mechanisms, not just the outcome.

Southern plantation owners continued to own most of the region's land 仍拥有该地区大部分土地 even after emancipation, so formerly enslaved people entered arrangements such as sharecropping 分成租佃 that produced dependence and debt rather than economic independence.

Then segregation 种族隔离, violence 暴力, unfavourable Supreme Court decisions 最高法院判决, and local political tactics progressively stripped away 逐步剥夺 the rights African Americans had gained. The result was a legal and social system that persisted into the twentieth century.

Vocabulary Train

English	Chinese	Pinyin
continued to own most of the region's land	仍拥有该地区大部分土地	réng yōng yǒu gāi dì qū dà bù fèn tǔ dì
sharecropping	分成租佃	fēn chéng zū diàn
segregation	种族隔离	zhǒng zú gé lí
violence	暴力	bào lì
Supreme Court decisions	最高法院判决	zuì gāo fǎ yuàn pàn jué
stripped away	逐步剥夺	zhú bù bō duó

5.12

Comparison in Period 5

Syllabus

5.12 Comparison in Period 5

Learning Objective	Review: Unit 5 Key Concepts
Unit 5.M Compare the relative significance of the effects of the Civil War on American values.	KC-5.1 The United States became more connected with the world, pursued an expansionist foreign policy in the Western Hemisphere, and emerged as the destination for many migrants from other countries. KC-5.1.I Popular enthusiasm for U.S. expansion, bolstered by economic and security interests, resulted in the acquisition of new territories, substantial migration westward, and new overseas initiatives. KC-5.1.II In the 1840s and 1850s, Americans continued to debate questions about rights and citizenship for various groups of U.S. inhabitants. KC-5.2 Intensified by expansion and deepening regional divisions, debates over slavery and other economic, cultural, and political issues led the nation into civil war. KC-5.2.I Ideological and economic differences over slavery produced an array of diverging responses from Americans in the North and the South. KC-5.2.II Debates over slavery came to dominate political discussion in the 1850s, culminating in the bitter election of 1860 and the secession of Southern states. KC-5.3 The Union victory in the Civil War and the contested reconstruction of the South settled the issues of slavery and secession, but left unresolved many questions about the power of the federal government and citizenship rights. KC-5.3.I The North’s greater manpower and industrial resources, the leadership of Abraham Lincoln and others, and the decision to emancipate enslaved people eventually led to the Union military victory over the Confederacy in the devastating Civil War. KC-5.3.II.i Reconstruction and the Civil War ended slavery, altered relationships between the states and the federal government, and led to debates over new definitions of citizenship, particularly regarding the rights of African Americans, women, and other minorities.

Learning Objective

Review: Unit 5 Key Concepts

Unit 5.M
Compare the relative significance of the effects of the Civil War on American values.

KC-5.1 The United States became more connected with the world, pursued an expansionist foreign policy in the Western Hemisphere, and emerged as the destination for many migrants from other countries.
- KC-5.1.I Popular enthusiasm for U.S. expansion, bolstered by economic and security interests, resulted in the acquisition of new territories, substantial migration westward, and new overseas initiatives.
- KC-5.1.II In the 1840s and 1850s, Americans continued to debate questions about rights and citizenship for various groups of U.S. inhabitants.
KC-5.2 Intensified by expansion and deepening regional divisions, debates over slavery and other economic, cultural, and political issues led the nation into civil war.
- KC-5.2.I Ideological and economic differences over slavery produced an array of diverging responses from Americans in the North and the South.
- KC-5.2.II Debates over slavery came to dominate political discussion in the 1850s, culminating in the bitter election of 1860 and the secession of Southern states.
KC-5.3 The Union victory in the Civil War and the contested reconstruction of the South settled the issues of slavery and secession, but left unresolved many questions about the power of the federal government and citizenship rights.
- KC-5.3.I The North’s greater manpower and industrial resources, the leadership of Abraham Lincoln and others, and the decision to emancipate enslaved people eventually led to the Union military victory over the Confederacy in the devastating Civil War.
- KC-5.3.II.i Reconstruction and the Civil War ended slavery, altered relationships between the states and the federal government, and led to debates over new definitions of citizenship, particularly regarding the rights of African Americans, women, and other minorities.

Source: College Board AP Course and Exam Description

The period's reasoning skill is comparison. Useful comparisons: the North and South before the war; the aims of Reconstruction against its outcomes; and the status of African Americans in 1865 against 1877.

Worked example (a real AP exam question). The 2023 exam set the long essay "Evaluate the extent to which the definitions of United States citizenship changed from 1865 to 1920." A strong thesis takes a position and acknowledges the reversal: "Definitions of citizenship changed substantially between 1865 and 1920, as the 14th and 15th Amendments established birthright citizenship and prohibited racial barriers to voting; however, segregation, violence and Supreme Court decisions made those definitions far less meaningful in practice for African Americans by 1900." Notice the shape: for a period that both expanded and reversed rights, a thesis must hold the legal change and the practical reversal together. Writing only about the amendments describes half the period.

5.12

Exam tips

Expansion is the cause of the sectional crisis. Every compromise from 1850 onwards is an attempt to answer whether slavery could expand.
Name the mechanism, not the mood. "Tensions rose" earns nothing; the Fugitive Slave Act, Dred Scott, and Bleeding Kansas do.
Give the Emancipation Proclamation its strategic role: it redefined the war's purpose and enabled Black enlistment.
Learn the three Reconstruction Amendments by what each one does; questions often turn on the difference between them.
For Reconstruction's failure, name sharecropping, segregation, violence, and Court decisions - the four mechanisms.
On comparison prompts, develop both sides. An answer that treats one side in a clause has answered half the question.

Period 5: 1844–1877

Manifest Destiny and Expansion

5.1 Contextualizing Period 5

5.2 Manifest Destiny

5.3 The Mexican–American War

Why Expansion Broke the Political System

5.4 The Compromise of 1850

5.5 Sectional Conflict: Regional Differences

5.6 Failure of Compromise

Secession and the Civil War

5.7 Election of 1860 and Secession

5.8 Military Conflict in the Civil War

5.9 Government Policies During the Civil War

Reconstruction

5.10 Reconstruction

The Failure of Reconstruction

5.11 Failure of Reconstruction

Comparison in Period 5

5.12 Comparison in Period 5

Exam tips

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