Which war was fought by the United States in the 1800s?

The Spanish-American War was indeed fought by the United States in the 1800s, specifically in 1898. This conflict marked a significant moment in U.S. history, as it resulted in the U.S. emerging as a global power. The war primarily stemmed from the struggle for Cuban independence from Spain, as well as the U.S. interests in the region and longstanding imperialist aspirations.

The outcome of the war led to the Treaty of Paris, where Spain ceded Guam, Puerto Rico, and the Philippines to the United States. This war highlighted the shift in U.S. policy from isolationism to a more aggressive imperialist approach, setting the stage for future U.S. involvement in international conflicts.

The other wars listed occurred in the 20th century and are unrelated to the specified time frame of the question.