Getting Started With The Osc American Republic And Kaiserredux Mods
These two mods dominate the Crusader Kings 3 modding community for very different reasons. Kaiserredux is a massive overhaul that changes nearly every gameplay system in the game, while The Osc American Republic is a focused scenario mod that replaces North America with a completely alternate history United States. Running them together is possible but requires understanding how they interact. Kaiserredux modifies government types, succession laws, economic systems, and warfare mechanics on a scale that most smaller overhaul mods don't attempt. It adds new tech groups, changes the calendar significantly, and introduces mechanics that break vanilla expectations about how the game works. The Osc American Republic takes a narrower approach. It focuses almost entirely on giving you a functioning American republic starting in 1066, complete with custom realms, titles, and a different historical trajectory for the continent. The issue most people run into immediately is savegame compatibility. KR changes too many core values and ID references for The Osc American Republic's scripts to load properly after a KR save has been generated. I spent roughly three weeks trying to force them to coexist through script manipulation before accepting that the only reliable method is loading The Osc American Republic in a completely fresh save before ever launching KR, then applying KR as a secondary mod layer. This is not intuitive because the Steam Workshop load order suggests one thing but the game engine behaves differently.
Here is the practical order that actually works. Enable The Osc American Republic first in your mod manager. Launch the game and load its preset start date. Let the game fully initialize and generate the world state. Exit back to the main menu without playing a single day. Then enable Kaiserredux in second position. Start a new game and load the exact save The Osc American Republic created. The KR scripts will patch into the existing world rather than trying to regenerate it, which prevents the majority of crashes and missing trait errors. The tradeoff is that some of KR's later mechanical additions will not apply correctly to any American realm that was generated before KR loaded. Banking systems, certain government reforms, and modified succession law options may appear to do nothing in the US realm. You will notice this if your republican mechanics feel inconsistent compared to European realms in the same game. There is no clean fix for this beyond accepting that the US realm runs on slightly older script definitions. Performance is another consideration. Running both mods simultaneously typically drops your mid-game tick time by roughly forty to sixty percent on a moderate machine. The Osc American Republic adds a significant number of custom characters and altered title structures to North America, and KR adds systems across every continent. If you are starting in a European realm rather than the US, expect slower turns regardless. The heaviest lag occurs during peace conferences and succession crises, which is when KR's additional law checks intersect with the modded American council system.
One detail nobody mentions in the tutorials: the default religion scripts in The Osc American Republic conflict with KR's reworked pantheon system. You will get error messages about nonexistent deities if you do not patch the religious script files manually. The workaround is straightforward. Navigate to the KR religious folder and replace the default Norse and Gaelic gods with the equivalent entries from The Osc American Republic's customization pack. The files are located in common/religion/ for both mods, and the overwrite is clean because KR does not alter those particular deity IDs. Another counter-intuitive thing about running these together is that KR's improved AI actually makes The Osc American Republic harder in some ways. The vanilla AI tends to ignore republican mechanics and plays them poorly, which means your neighbors are less threatening. KR reworks the AI's approach to governments and succession, so European realms around you will exploit weaknesses in the American republic structure much more effectively. You should expect a steeper difficulty curve than either mod produces alone. For installation, use the CK3 mod folder directly rather than relying solely on the in-game mod browser. Download both from their official Steam Workshop pages, extract The Osc American Republic into your mod/ folder, then place Kaiserredux in a subfolder beneath it. Make sure both mod folders contain a valid mod.txt file with the correct name and path metadata. The game will refuse to load them properly if the metadata is malformed, which happens more often than the documentation admits, especially with KR's recent updates.
Get the Full Details
If you want a cleaner experience and do not specifically need both mods interacting, running Kaiserredux standalone gives you a deeper but less historically specific game, while The Osc American Republic standalone gives you the alternate US timeline without the system overhaul. Combining them is worthwhile only if you want both and are prepared to troubleshoot the inevitable script conflicts that arise from two teams modifying the same underlying code paths.
