The American Civil War (April 12, 1861 – May 9, 1865) was a civil war in the United States between the Union (states that remained loyal to the federal union, or "the North") and the Confederacy (states that voted to secede, or "the South"). The central cause of the war was the status of slavery, especially the expansion of slavery into territories acquired as a result of the Louisiana Purchase and the Mexican–American War.
Simple map of the states in the Union "the North":
Simple map of the Southern slave states which remained in the Union:
Simple map of the Union territories not permitting slavery:
Simple map of the Confederacy "the South":
Simple map of the Union territories claimed by Confederacy: