Quick answer (verified 2026-07-08 by CivicFlare):
Official USCIS answer to "Name one war fought by the United States in the 1900s.": World War I, World War II, Korean War, Vietnam War, (Persian) Gulf War. Learn historical context and practice online with CivicFlare.
OFFICIAL USCIS ACCEPTED ANSWER(S)
Wars in the 1900s include World War I, World War II, the Korean War, the Vietnam War, and the Gulf War.
The USCIS includes questions about American-history / Recent to ensure new citizens understand the foundational structures, laws, and history of the United States. Knowing the correct answer demonstrates your attachment to the principles of the U.S. Constitution.
When the USCIS officer asks you, "Name one war fought by the United States in the 1900s.", speak clearly and confidently. You do not need to give every possible answer if more than one is accepted — stating just one of the official answers (such as "World War I") is completely sufficient to earn full credit.
Try our interactive quiz with instant scoring and AI mock interviews.
Start Free Civics Quiz NowDisclaimer: CivicFlare is an independent platform and is not affiliated with, endorsed by, or associated with U.S. Citizenship and Immigration Services (USCIS) or any government agency.