Name one war fought by the United States in the 1800s.

The War of 1812 was fought between the United States and Great Britain soon after the American Revolution. Americans fought over issues like trade limits and sailors being forced into the British navy, and the fighting included battles on land and at sea. It helped strengthen U.S. national identity even though neither side clearly won.

The Mexican-American War was fought from 1846 to 1848 between the United States and Mexico. It ended with the Treaty of Guadalupe Hidalgo, and the United States gained large areas in the Southwest, including what is now California and New Mexico.

The Civil War was fought from 1861 to 1865 between the North (Union) and the South (Confederacy). It was mainly about slavery and whether states could leave the United States, and it ended with the Union preserved and slavery abolished.

The Spanish-American War was fought in 1898, near the end of the 1800s. It began after rising tensions between the United States and Spain, especially over Cuba. The war led to the U.S. gaining control of places like Puerto Rico, Guam, and the Philippines.