The war fought between the northern and southern states of the United States from 1861 to 1865 is known as the American Civil War. This conflict primarily revolved around the issues of slavery and states' rights, with the southern states seceding from the Union to form the Confederacy. The war resulted in significant loss of life and had profound effects on the United States, ultimately leading to the abolition of slavery with the Emancipation Proclamation and the passage of the Thirteenth Amendment. The Civil War also set the stage for the Reconstruction era, during which efforts were made to integrate formerly enslaved people into society.