当农民和平民起义反抗他们的法定领主并且开始袭击省份的地产时，一场 叛乱（英文：revolt） 发生了。
同拥有者不同宗教或文化的省份，叛乱风险（英文：Revolt risk）增加。如果它们不仅不同文化而且是不同文化组（同样地，不仅不同宗教而且不同宗教组），则叛乱风险增加更多。
逝往神灵前
下文描述的是没有 
逝往神灵DLC的旧系统。
当叛乱风险判定通过时，一群由轻步兵、弓箭手，通常还有骑兵组成的叛军在这个省份中出现。它的规模是该省最大驻军的1.25倍，对“所有人”都怀有敌意。如果叛军成功征服一个省份，之后将可能发生摧毁建筑，或者当地土地拥有者受伤或被杀的事件。一个占领时间足够长的省份甚至可以脱离或加入另一个国家。
通常，如果叛军在一位拥有多个地产的附庸公爵的土地上产生，他将调集他自己的征召兵和近卫军来解决叛军。但从根本上来说，处理叛军是领主的义务，并且你的伯爵级别的封臣经常不能够处理大量叛军。叛军通常在输掉一场战斗后就会解散，避免了在地图上到处追赶他们。
逝往神灵
若 逝往神灵激活，叛军有四种类型：农民叛乱，宗教叛乱，异端叛乱和解放叛乱。叛军有一位临时头衔为公爵级的领袖，他向此国宣战，但同时也对所有其他独立统治者怀有敌意。
所有叛乱事件在月初第一天触发。叛乱在一个省份发生，同时产生和其最高领主的征召兵同等规模的军队，和冒险家的方式一样。如果有正在进行的同样目标的叛乱，额外的部队将加入已经存在的叛乱而不是重复宣战。如果你有100%的战争分数（通常是因为消灭了敌军），战争结束。
叛乱和其他任何战争的效果一样（例如打断盛宴和其他要求你处于和平的事件链，并且组织任何人篡夺你的头衔）。一个例外是叛乱不打断 
见证领地范围野心。它们会打断 
塑造血脉野心的和平年份计数。
如果叛乱胜利，叛乱头衔被摧毁而领袖独立。如果它失败，领袖被防御方囚禁并获得“意志消沉”修正，使得他们作为无用的未来的领导者。
尽管叛乱风险取决与省份和当地统治者的差异，但叛军使用的CB取决于省份和最高领主的差异：
- 农民叛乱
- 一次农民叛乱由一位随机产生的出身低贱，和省份同宗教文化，拥有
特质的角色领导。头衔和CB被称为“[省份名称]农民叛乱”（如，“康沃尔农民叛乱”）。一旦成功，仅目标省份被篡夺。 - 宗教叛乱
- 如果省份宗教和最高统治者是不同宗教组，叛乱可能是一次宗教叛乱，由一位随机产生的和省份同宗教文化的角色领导。头衔和CB被称为“[省份名称][宗教]叛乱”（如，“叙利亚东正教叛乱”）。一旦成功，进攻方夺取全部已占领的地产（和被占领省份内的地产）和目标公国的地产（除非其被正确宗教的角色持有，可以被附庸而不是篡夺）。进攻方自动篡夺公爵头衔，如果其被防御方持有或不存在。
- 异端叛乱
- 类似于宗教叛乱，当省份宗教是最高领主宗教的异端时，可能触发。由一位拥有
特质的角色领导。 - 解放叛乱
- 一种更危险的叛乱，其目标是一整个法理王国，此王国的头衔当前不存在但曾经存在（可能早于游戏开局时间）。当省份文化不同于最高领主，而“王国文化”（即法理王国的传统文化）与省份文化相配时，此类叛乱可能发生。其名誉头衔是“解放[王国]叛乱”（如，“解放威尔士叛乱”）。如果叛乱胜利，他们获得占领的地产和所有领主控制的目标王国的领土。如果产生的国家有5个或更多的省份，这位新独立的统治者将创建或篡夺此王国头衔（除非其被一位未涉入战争的统治者持有）。
叛乱风险
Each province has a revolt risk that determines the chance of a revolt breaking out.
Due to differences between the province population and the local ruler (or regent):
- +1%: Different culture (of same culture group)
- +2%: Different culture group
- +1%: Different religion (of same religion group)
- +2%: Different religion group
- +3%: Heresy
Due to other circumstances:
- +4%: Isolated County (not the holder's capital, and not adjacent to another demesne province)
- +4%: Nomad agitation in provinces taken from
nomadic realms
Due to temporary province modifiers, triggered by events and shown as red icons:
- +5%: Incompetent ruler (caused by a ruler being in debt)
- +5%: High taxes (caused by Collect Taxes mission)
- +5%: Triple Taxation! (caused by Extort Peasants with the Build War Chest ambition)
- +10%: Cultural unrest
- +10%: Religious tension (can be triggered during Proselytize mission, or by low moral authority in Indian religions)
- +50%: Religious unrest
- +50%: Heretic stronghold (province where a heresy appeared spontaneously)
- Various crises during epidemics, with The Reaper's Due
When a province provides a reinforcement to an ongoing revolt such as religious revolt, the province gets recent uprising which lowers the revolt risk by 100% for 5 years.
策略
- Lower revolt risk:
- Spread your culture, or keep vassals of the same culture as their province
- Spread your religion, or keep vassals of the same religion as their province
- Keep moral authority high to avoid having heretic strongholds appear.
- Convert counties quickly, especially if the religion of the counties have a low MA
- Crush religious revolts quickly, lest additional troops join the ongoing revolt.
- On the other hand, it might be useful to let revolt gain strength, if you have a lot of rebellious provinces. Any province which joins an ongoing revolt won't rebel again for 5 years.
- Offer white peace to rebel leaders once you have destroyed approximately half of their army. You still get to imprison the leader. Only go for full victory if you need the additional prestige or piety.
- While you cannot call allies to help you with revolts, you can call them to join you in another war, and use their attached armies against the rebels.
- If you cannot spare the soldiers to defeat an independence or peasant revolt in your de jure territory, an alternative solution is to surrender before too much damage is done. You will take a prestige hit, but if you can afford it you will immediately gain a variety of claims on the errant territory, allowing you to quickly reconquer it with your allies' support. This also severely weakens the enemy, especially in the case of peasant rebellions: they will suffer new administration penalties to levies and taxes, and much of the active army will have immediately dispersed upon their earlier "victory". In addition, as you were the defender during the preceding war, the relevant truce only binds the rebel leader as the aggressor.