APUSH Period 7 — Empire, Reform and the First World War, 1890–1920

Period 7 of AP United States History, 1890 to 1945, carries between 10 and 17 percent of the exam and is the longest period in the course. This material covers its first three decades, when the United States became an overseas power, reformers rewrote the Constitution four times in seven years, and a world war changed American society at home.

The first part follows the turn to empire: Alfred Thayer Mahan's case for sea power and bases; the war with Spain in 1898 and the path from the Teller Amendment to the Platt Amendment in Cuba; the annexation of the Philippines, the war against Filipino independence and the arguments of the Anti-Imperialist League; the Open Door notes on China; and Theodore Roosevelt's corollary to the Monroe Doctrine, which turned a warning to Europe into a claim to police the hemisphere.

The second part turns to Progressive reform: the muckrakers and The Jungle, which produced the food laws of 1906; the Sixteenth to Nineteenth Amendments and what each was meant to fix; and the long campaign for woman suffrage, won by combining state campaigns, lobbying, war work and the pickets of the National Woman's Party.

The last part covers the First World War and its aftermath: why the United States entered in 1917, why the Senate rejected the Treaty of Versailles and the League of Nations, the Great Migration of black Southerners to Northern cities, and the first Red Scare with its strikes, bombings and raids.

The twelve quiz questions include public-domain sources quoted in the question, such as Roosevelt's 1904 message to Congress and Wilson's war message, and ask how a policy changed an older one, what caused a development and what followed from it. The explanations deal with frequent chronology mistakes, such as treating the Lusitania as the immediate cause of war in 1917 or placing the vote for women in Reconstruction.

The eighteen flashcards run from the annexation of Hawaii to the Palmer Raids, with dates and significance.

The category's material on 1865 to 1945 covers Progressive trust regulation, wartime civil liberties, the 1920s, the New Deal and the Second World War home front; a companion material in this category covers the 1920s to 1945 in more depth. Use this one during Unit 7 in class or in review before the May exam.

• Explain the strategic, economic and ideological arguments for and against American overseas expansion after 1890
• Describe American policy toward Cuba, the Philippines, China and Latin America from 1898 to 1904
• Explain what the Progressive amendments and the 1906 food laws were meant to reform
• Explain why the United States entered the First World War and why the Senate rejected the League of Nations
• Describe the Great Migration and the causes of the first Red Scare

Practice material written by Zestly, based on the College Board AP U.S. History course framework (course and exam description effective fall 2026), Unit 7, Period 7: 1890–1945, topics on imperialism debates, the Spanish–American War, the Progressives, World War I military and home front. Quoted sources are presidential messages of 1904 and 1917 (public domain).