- New Start date: 769.
- Viceroyalty: non-tribal emperor tier characters will be able to appoint viceroys (lifetime governorship, the title goes back to the liege on death).
- Custom kingdoms and empires (3 duchies or 1 duchy and certain realm size to form a custom kingdom, 3 kingdoms or 1 kingdom and certain realm size to form a custom empire)
- Narrative events to tell historical stories between Charlemagne, Carloman and related characters.
- Chronicles of your dynasty
- Special features of Zuni religion
- Graphics for early Western, Eastern and Muslim units
- Tribal holdings (buildings built with prestige, vassals need to be called as allies) that can potentially become feudal castle or merchant republic city.
- Centralization, a set of laws balancing a new vassal limit vs demesne size limit.
- Legalism cultural technology only unlocks new laws. Short reign penalty is moved to the Majesty technology.
- Regency overhaul: new Designated Regent honorary title, regent traits and his opinion of the ruler matters, in particular for unlocking diplomatic actions.
- Elective gavelkind succession law
- Assassination diplomacy action removed.
- Seasonal effects: attrition increased with snow
- New UI for selecting start date and initial character.
- Spectator mode
- Cultural melting pots and decisions
Upon release, Charlemagne was extremely well received. Critics praised the additional time period, the implementation of seasonal changes and changes to assassination and law systems. It currently holds a score of 80/100 on metacritic.
- CM is the first expansion with Johan Lerström as project lead.
Main article: Developer diaries
|No.||Title and Link||Description||Date|
|1||Let's get Early Medieval||New cultures and religion changes introduced to properly represent new start date in year 769.||2014-09-17|
|2||Kings, Queens and Murderers||Custom kingdoms and empires, chronicle and changes to the plot mechanism related to assassination.||2014-09-24|
|3||Ruling the Unruly||Vassal limit, centralization law and viceroys. Changes in regency system.||2014-10-01|
|4||The Tribes||Holding and government type created to properly represent tribal nations.||2014-10-08|