Which war was fought between the North and South regions of the United States?

The American Civil War was fought between the Northern states (the Union) and the Southern states (the Confederacy) from 1861 to 1865. The primary cause of the conflict was the long-standing debate over slavery and states' rights. The Southern states wanted to maintain the institution of slavery for their agrarian economy, while the Northern states opposed its expansion into new territories. The war had profound implications for the nation, ultimately leading to the preservation of the Union and the abolition of slavery.

In contrast, the Revolutionary War was fought between the American colonies and Great Britain from 1775 to 1783, as the colonies sought independence. The War of 1812 was largely a conflict between the United States and Great Britain, centered on maritime issues and territorial expansion. The Spanish-American War occurred in 1898 and dealt with the U.S. intervention in Cuba and territorial expansions in the Caribbean and Pacific. Each of these wars addressed different issues and involved different regions and nations, making the American Civil War distinct in its focus on the internal division within the United States.