The American Civil War was a conflict between the Northern and the Southern United States. The states broke off individually at first, but quickly came together to form the Confederate States of America. The reasons for exactly why it occurred are debated, course the textbook gives a very one-dimensional answer—slavery. I think why the narrative shifted like that is two-fold, one it serves as a cudgel for the South and whites in general that they should constantly apologize and feed bad for slavery, the second is economic because unified country is better business. Probably more realistically it was a large number of things that came together, economic interests were at stake, cultural interests were at stake, and political interests were at stake. Economic was slavery and tariffs. Cultural was the the mostly agrarian culture the South had. Political was the decreasing political influence the South had as more states were being added to the Union and population growth not as fast as the North. Many of the Southern states also didn’t see the Union as something which they were obligated to be a part of, so it wasn’t thought of an act of treason and treachery, therefore the Northern invasion of the South was unprovoked. Also, I think it’s important to recognize, most Northern soldiers didn’t see themselves as fighting to free the slaves. Wasn’t out of some moral reason the North didn’t own slaves, it was just they didn’t have a suitable climate. I think it’s also telling how willing Lincoln was to reintroduce the rebellious states back into the Union. The North launches an invasion of the South, the war ends up going on for five years and brings ruin to the South for decades to come. South had better soldiers and officers, but the North leveraged its industry. Grant marched to Richmond not through some brilliant tactics, but by making use of the North’s superior logistics. The Confederacy only really had one effective army. Their pride and Richmond’s proximity to Washington D.C. came back to bite them.
Lincoln had wanted to quickly accept and seat the states which had succeeded. This was all put to a stop by the assassination of Lincoln. Johnson became president and growing feuds began to break out between the Republicans in congress and the president. As the Republicans got more and more fed up with Johnson, they began to grow more and more radical. In the end, the whole policy of the Northern government in the South was all over the place. With the Emancipation Proclamation slaves were freed some places and not others. Sherman had given land to freedmen, but that was later revoked. The government never really did figure out what they should do with the former slaves. Citizenship and voting rights were extended, but the extent to which the Northern army was able to police and carry out the will of the government was always a bit shaky. Southerners still bitterly resented their occupiers.
I think it depends on what’s you constitute as a success. Today all the states that split apart are part of the United States with little talk of independence. For upper-middle class Southerners the war and reconstruction were wretched times to live in. For more humble farmers maybe things didn’t change all that much. If you’re talking about the Slaves then it’s mixed. On the one hand you can list what they achieved, on the other you can list maybe potential shortcomings. I think labeling reconstruction a failure because of the failure to satisfactory accommodate black people is a bit of a modern revisionism, making it out like the federal government was mostly a force for abolition and the furtherment of the dignity of African-Americans. Ultimately, the South was made up of mostly Southerners and it would’ve taken a lot more competence and conscious effort for it not to go back to being run that way, especially after the war. I think the bigger problem was just poverty. The reality is is that poverty usually doesn’t create exactly create the most progressive attitudes. And it took the South decades to rebuild from the devastation from the Civil War.