AP US History — Unit 6: Period 6: 1865–1898

What AP US History Unit 6 covers

The College Board Course and Exam Description breaks Unit 6 into 13 topics:

1. 6.2 Westward Expansion: Economic Development
2. 6.3 Westward Expansion: Social and Cultural Development
3. 6.4 The New South
4. 6.5 Technological Innovation
5. 6.6 The Rise of Industrial Capitalism
6. 6.7 Labor in the Gilded Age
7. 6.8 Immigration and Migration in the Gilded Age
8. 6.9 Responses to Immigration in the Gilded Age
9. 6.10 Development of the Middle Class
10. 6.11 Reform in the Gilded Age
11. 6.12 Controversies over the Role of Government
12. 6.13 Politics in the Gilded Age
13. 6.14 Continuity and Change in Period 6

AP US History Unit 6 practice questions

• In 1869, two railroad companies met at Promontory Point, Utah and drove a golden spike — one built east, one built west. Who laid the track, and why does this single rail line matter beyond transportation?

  The Transcontinental Railroad was built largely by Chinese and Irish immigrant labor. Chinese crews built the Central Pacific and Irish the Union Pacific — creating a national market, accelerating western migration, and making industrial America possible.

• The Homestead Act offered 160 free acres to anyone who farmed it for 5 years. Sounds like the American Dream — so why did roughly two-thirds of independent homesteaders go bankrupt?

  The plains were brutal — drought, insects, isolation, no timber — and railroads gouged on shipping. Equipment was expensive, and small family farms couldn't compete with corporate operations consolidating millions of acres.

• After Reconstruction collapsed, ~40,000 Black Americans fled the South for Kansas in the 1880s, naming themselves after the biblical Exodus. Who were they — and what were they running from?

  The Exodusters fled KKK violence, Jim Crow, sharecropping debt, and the collapse of civil rights. After the Compromise of 1877 ended Reconstruction, Kansas offered free Homestead land and escape from white supremacist terror.

• The US signed treaties recognizing Indigenous sovereignty over the Plains. Then gold was discovered on Indigenous land. What happened next — and what pattern does this reveal?

  The US broke every treaty — Fort Laramie recognized Indigenous sovereignty, but gold changed that. Congress opened the land to settlers, backed by military force: treaty, violation, renegotiation on worse terms, repeat.

• The Dawes Act (1887) divided reservations into 160-acre individual plots and offered citizenship — IF Indigenous people abandoned their language, religion, and culture for 25 years. Was this generosity or destruction?

  Destruction — the Dawes Act broke up communal land and forced cultural assimilation. It ended recognition of tribal sovereignty, gave 'surplus' land to white settlers, and cost Indigenous people 2/3 of their remaining land.

• In 1890, the US Army killed ~250 Lakota Sioux at Wounded Knee — many women and children. Often called the 'end' of Indigenous resistance. What spiritual movement prompted the confrontation?

  The Ghost Dance — a spiritual movement, inspired by the prophet Wovoka, promising Indigenous renewal. It promised the return of Indigenous ways and the departure of white settlers, but the US treated it as a military threat, answering with the Wounded Knee Massacre.

• In 1893, historian Frederick Jackson Turner argued the frontier had shaped American democracy and individualism — and it was now CLOSED. Why did this thesis matter?

  Turner's Frontier Thesis called the frontier a 'safety valve' for restless Americans. When life got hard people moved west, but with the frontier closed (Census of 1890) that outlet was gone — risking unrest and pushing America to look OVERSEAS for new frontiers.

• Homer Plessy was 7/8 white. He deliberately sat in a whites-only train car in Louisiana to challenge segregation in court. The Supreme Court ruled against him. What was the ruling — and how long did it stand?

  Plessy v. Ferguson (1896) ruled that 'separate but equal' facilities were constitutional. It gave legal cover to Jim Crow across the South and stood for 58 years, until Brown v. Board overturned it in 1954.

+ 57 more AP US History cards in the app.

Key terms in Unit 6

These 12 terms show up in the Unit 6 cards. Each one links to its definition in the AP US History key-term reference.

• Chinese Exclusion Act
• Compromise of 1877
• Gospel of Wealth
• Great Depression
• Horizontal integration
• Japanese Internment
• Manifest Destiny
• Plessy v. Ferguson
• Republican motherhood
• Treaty of Guadalupe Hidalgo
• Vertical integration
• Wounded Knee Massacre