A major cause of the Civil War was an underlying division between the North and South; slavery. Abraham Lincoln's Emancipation Proclamation freed slaves in areas that had succeeded from the Union. As President of the United States, his main purpose was to keep the Union together. However, the Civil War had created a division between the North and South. Lincoln believed that announcing the Emancipation Proclamation after a Union Victory would invite freed slaves to join the Union army and leave Southern States.
