The federal states and union were redefined predominantly in the north after the Civil War. Also, the abolition of slavery was felt first in the north and was much less resented by northern citizens. The north also experienced an economic boom.
The Civil War had a very bad effect on both the North and the South. Many cities in the South had to be rebuilt from the ground up. Many people in the South moved to the North and it caused major overcrowding.
The economic consequences of the Civil War are largely due to Northern control of the federal government during and after the war. It stimulated the industrial revolution in the North. The effects were devastating in the South.