Hang on, you already said that “control of (Slavery) that system that was central to the (Civil War) conflict.”
Below are five other causes of the Civil War. To be fair, each of these causes was impacted by the institution of slavery to one degree or another. But each cause also existed apart from the institution of slavery.
1. Sweeping Economic Changes
2. The Union Was Rapidly Changing Amidst Political Upheaval (because of expansion)
3. There Was a Breakdown of Decorum and Civil Discourse (Kinda like what is happening today with the left and right)
4. Fundamental Disagreement on Constitutional Principles (again...kinda like today)
5. Rapidly changing economy precipitated by a suddenly expanding global marketplace, political upheaval in a period of national growth