History of the United States (1849–1865)
The history of the United States from 1849 to 1865 was dominated by the tensions that led to the American Civil War between North and South, and the bloody fighting in 1861–1865 that produced Northern victory in the war and ended slavery. At the same time industrialization and the transportation revolution changed the economics of the Northern United States and the Western United States.
Source: Wikipedia — History of the United States (1849–1865) (CC BY-SA 4.0)