What years does AP US History Period 6 cover?

Period 6 covers 1865 to 1898, the era known as the Gilded Age. The College Board notes that historical developments can begin before and extend beyond these approximate dates, so expect some overlap with Reconstruction at the start and with the Progressive Era at the end. On the exam Period 6 falls in Unit 6 and is weighted at roughly 10 to 17 percent of the multiple choice section.

What are the Key Concepts for AP US History Period 6?

There are three. Key Concept 6.1 is that technological advances, large-scale production, and new markets encouraged the rise of industrial capitalism. Key Concept 6.2 is that the migrations accompanying industrialization transformed urban and rural areas and caused dramatic social and cultural change. Key Concept 6.3 is that the Gilded Age produced new cultural and intellectual movements, public reform efforts, and political debates over economic and social policy.

What is the difference between vertical and horizontal integration?

Vertical integration, used by Andrew Carnegie in steel, means controlling every stage of production from raw materials to finished product. Horizontal integration, used by John D. Rockefeller in oil, means buying up or destroying rival firms in the same business until one company dominates the industry. Rockefeller organized his empire as a trust, which placed many companies under one management, and Standard Oil controlled around ninety percent of American refining.

Why did the Populist movement fail?

The People's Party, or Populists, demanded free silver, government ownership of railroads, a graduated income tax, and the direct election of senators in their 1892 Omaha Platform. The movement peaked in the election of 1896, when the Democrats adopted free silver and nominated William Jennings Bryan, but Bryan lost to the Republican William McKinley. With its central issue defeated and its support absorbed by the Democrats, Populism faded as a separate party, though many of its demands later became Progressive Era law.

How was the Gilded Age West settled?

Federal policy drove western settlement. The Pacific Railway Act funded the transcontinental railroad, completed in 1869 at Promontory Summit, Utah, and the Homestead Act of 1862 offered 160 acres to settlers who farmed the land. Mining strikes and the open-range cattle industry built booming economies. This came at a devastating cost to American Indians, who were forced onto reservations, saw the buffalo destroyed, and lost much of their remaining land to the Dawes Act of 1887.

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AP US History Period 6 (1865 to 1898): the Gilded Age unit guide

A complete unit guide to AP US History Period 6 (1865 to 1898), the Gilded Age. Maps the College Board Key Concepts 6.1 to 6.3, walks through industrial capitalism, the settlement of the West, immigration and the cities, labor, and Populism, and links to the dot points and the paired quiz.

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Jump to a section

What Period 6 is about
The College Board Key Concepts
The dot points in this unit
How Period 6 is tested
Study strategy for this unit
Pair this with the quiz

What Period 6 is about

AP US History Period 6 (1865 to 1898) is the Gilded Age, the era when the United States became an industrial and urban power. After the Civil War, a national railroad network, abundant resources, new technology, and a flood of cheap labor made the nation the world's leading industrial economy, dominated by giant corporations and trusts. Industrial growth pulled millions into the cities, fed by a "new immigration" from southern and eastern Europe, while settlers and the federal government pushed into the West and dispossessed American Indians. The wealth and inequality of the age produced bitter labor conflict, the agrarian revolt of Populism, and the first debates over whether government should regulate corporate power. This guide maps the unit, then links to a dot point for each major topic.

The College Board Key Concepts

The CED organizes Period 6 around three Key Concepts. Anchor your study to them.

Key Concept 6.1: the rise of industrial capitalism

Technological advances, large-scale production methods, and the opening of new markets encouraged the rise of industrial capitalism. The transcontinental railroad, the Bessemer process for steel, and inventions such as the light bulb and telephone built a continental market. Entrepreneurs such as Carnegie (vertical integration) and Rockefeller (horizontal integration and the trust) concentrated wealth and power, defending it with Social Darwinism and the Gospel of Wealth, while the weak Sherman Antitrust Act (1890) marked the first federal response. See The Rise of Industrial Capitalism.

Key Concept 6.2: migration transforms urban and rural America

The migrations that accompanied industrialization transformed both urban and rural areas. The new immigration from southern and eastern Europe filled the factories and cities, creating ethnic neighborhoods, a new middle class, and the political machine, and provoking a nativist backlash and the Chinese Exclusion Act (1882). In the West, railroads, the Homestead Act, and the army opened the land to settlers and dispossessed American Indians through the reservation system, the destruction of the buffalo, and the Dawes Act (1887). See Immigration and the Cities and The Settlement of the West.

Key Concept 6.3: reform, culture, and political debate

The Gilded Age produced new cultural and intellectual movements, public reform efforts, and political debates over economic and social policy. Workers organized the Knights of Labor and the AFL and waged the great strikes; farmers built the Populist movement and its Omaha Platform; and the nation debated civil service reform, the tariff, and the money question. See Labor in the Gilded Age and Politics and Reform in the Gilded Age.

The dot points in this unit

Our complete coverage of Period 6, one page per major topic:

How Period 6 is tested

Period 6 is a rich source of multiple choice and SAQ material, and it appears regularly in the DBQ and LEQ. Favorite themes include the rise of big business and the "robber baron" versus "captain of industry" debate, the impact of the railroad and the settlement of the West, the experience of immigrants and the nativist reaction, the labor movement and the great strikes, and the Populist challenge. Because the period sets up Progressive reform, examiners often ask continuity and change questions linking the Gilded Age forward to Period 7.

AP US History Period 6 (1865 to 1898) is the Gilded Age, when the United States became the world's leading industrial and increasingly urban economy. College Board Key Concept 6.1 covers the rise of industrial capitalism (railroads, steel, Carnegie and Rockefeller, trusts, Social Darwinism, the weak Sherman Antitrust Act); 6.2 covers the migrations that transformed America (the new immigration and the cities, the settlement of the West, and the dispossession of American Indians through reservations and the Dawes Act); and 6.3 covers reform and political debate (the labor movement and its great strikes, and the Populist revolt that climaxed in the election of 1896). The unit is heavily tested through multiple choice, SAQs, and continuity and change essays linking the era to the Progressive reform of Period 7.

Study strategy for this unit

Learn the period as a connected transformation. Industry needed labor (immigration and the cities), markets and resources (the West), and produced inequality (labor conflict and Populism). Tie the topics together rather than memorizing them in isolation.
Master the big contrasts. Vertical versus horizontal integration, Knights of Labor versus AFL, old versus new immigration, gold versus silver. Examiners love these.
Pin the dates. Transcontinental railroad 1869, Chinese Exclusion Act 1882, Dawes Act 1887, Sherman Antitrust Act 1890, Omaha Platform 1892, Plessy v. Ferguson and the election of 1896.
Practice the continuity and change framing. Be ready to argue that the economy was revolutionized while racial inequality deepened and laissez-faire politics largely persisted. See Continuity and Change in Period 6.
Drill the rubrics. Apply the technique from our guide on how to write the APUSH DBQ and LEQ.

Pair this with the quiz

Test your grasp of the Gilded Age with the Period 6 quiz, then work through the dot points above and review the official Course and Exam Description at AP Central.

Sources & how we know this

AP United States History Course and Exam Description — College Board (2020)