What might have happened had the Civil War not
occurred?

If the Civil War had not happened, we likely would not have any of the Southern states in our Union.

Explanation:

One of the largest catalysts for the Civil War was that South Carolina and other Southern states wanted to secede. The North had used force to prevent this, which started the Civil War. If the North had not done this, the war would not have occurred, and the South would not still be part of the Union. There would have been no forces to bring those states back into the Union, so our country would likely be a lot smaller.

There is also a chance that the states that seceded could still have slavery even modern day.