Civil wars may occur based on the popular support for a certain ideology. If the support for a certain ideology that is not currently ruling in a country grows too large, they will start demanding a change of government. If the player ignores the clamor for reform or actively refuses to allow reform the chance of a civil war breaking out will grow. It will then start with an event allowing the player to choose their side. It is also possible for the growing ideology to start a coup, which would allow for a peaceful transition.

Once a civil war breaks out, the country breaks into two separate entities. How it divides varies for non-scripted civil wars; the amount of land given to a side depends on the popular support for the ideology leading it. For this reason, for effective coups, it is recommended that the "Stage a coup" action is coupled with the "Boost party popularity", as increasing the support for an ideology higher will also increase the size of the break-away state. The two sides, the loyalists and the rebels, immediately enter a state of war with each other, fighting to unite the country under their flag. Once started, a civil war will act as a normal war with victory points eventually leading to capitulation as they fall. The only difference being that there are no occupation laws for occupied territory owned by the other side.




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