🇺🇸ap us history review

Closed frontier

Written by the Fiveable Content Team • Last updated August 2025
Verified for the 2027 exam
Verified for the 2027 examWritten by the Fiveable Content Team • Last updated August 2025

Definition

The perception in the 1890s that the American Western frontier had been fully settled and developed, prompting imperialists to argue for overseas expansion as a new outlet for American growth and ambition.

AP course connection

Topic 7.2: 7.2 Imperialism: Debates

Unit 7

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