Do you think the Civil War was maining over slavery or something else?

Slavery played the central role during the American Civil War. The primary catalyst for secession was slavery, especially Southern political leaders' resistance to attempts by Northern antislavery political forces to block the expansion of slavery into the western territories.

I think the main cause of the civil war was slavery because the south was pro slavery and the north was anti slavery and didn't like that Abraham Lincoln had one because he did not like slavery I want to get rid of it so they decided to try and break off and create their own country where slavery was allowed which caused the civil war