Which war was fought from 1861 to 1865?

The correct answer is the Civil War, which was fought from 1861 to 1865. This conflict was primarily between the Northern states (the Union) and the Southern states (the Confederacy) of the United States. The war arose from tensions surrounding issues such as slavery, states' rights, and economic disagreements. It was a significant turning point in American history, leading to the preservation of the Union and the abolition of slavery.

The other options represent different historical conflicts. World War I occurred from 1914 to 1918 and involved multiple nations across the globe. The Revolutionary War took place from 1775 to 1783, where the Thirteen Colonies fought for independence from British rule. World War II lasted from 1939 to 1945, involving most of the world’s nations in a broad conflict that followed the rise of totalitarian regimes. These wars occurred in different contexts, time periods, and with different international implications than the Civil War.