- Tsardoms and Principalities: New ranks of Russian government with new abilities and, for Tsars, strong bonuses including the right to claim entire states.
- Iconography: Commission great religious icons for the Orthodox church, boosting your empire’s power depending on the saint you choose to revere.
- Metropolitans: Consecrate highly developed provinces with Metropolitans, adding to the authority of the Orthodox church, but for a cost.
- Streltsy: Special Russian soldiers that excel in combat, but raise the cost of stabilizing your empire.
- Siberian Frontier: Russian nations can slowly colonize uninhabited border regions, with no fear of native uprisings.
- Third Rome Content Pack: Adds 48 new unit models to nations in and around the Russian borders.
- Added new Tsardom government type.
- Added new Principality government type.
- Added Veche Republic government type.
- Added Tsardom events.
|1||历史研究||Trin Tragula, EU4's content designer, on the process of historical research done with EU4 and its expansions||2017-05-02|
|2||Bonus Development Diary||Sneak peek at features for 1.22, including Press Sailors subject interaction and changes for blockades, marches, Aristocracy ideas and Buddhism||2017-05-05|
|3||The Russian Principalities||Trin Tragula, EU4's content designer, reveals setup changes in the Greater Russian region coming in 1.22||2017-05-09|
|6||Icons and Metropolitans||Jake elaborates on the expanded mechanics for the followers of the Orthodox faith||2017-05-30|
|7||Custom Nation Designer and Achievements||Jake explains the novelties in the nation designer and introduces new achivements (from his balcony)||2017-06-06|
|8||Third Rome Update||The Third Rome (1.22) changelog||2017-06-13|
|9||Changing of the Guard||Anna "Anona" Norrevik on changes within the team and introduction of the new project lead Linda "Fogbound" Tiger||2017-06-20|
|10||EU4的音效||David，声音设计师，the sound designer, on complementing the EU4 interface with the right sound effects||2017-06-27|
- Forum, Europa Universalis IV to Get Immersion Pack "Third Rome", 2017-05-12
- Forum, EU4 - Development Diary - 13th of June 2017, 2017-06-13