The Civil War questline runs parallel to the main quest, but you need to interact with it in order to kickstart the last part of the main quest.
You can beat the game without finishing it by getting everyone to do a meeting at the Greybeards’s place to discuss a cease-fire while you do dragonborn shit, which is a neat quest idea, just not executed very well. If you finish the Civil War quest you skip this entirely.
The Civil War questline runs parallel to the main quest, but you need to interact with it in order to kickstart the last part of the main quest.
You can beat the game without finishing it by getting everyone to do a meeting at the Greybeards’s place to discuss a cease-fire while you do dragonborn shit, which is a neat quest idea, just not executed very well. If you finish the Civil War quest you skip this entirely.