[2021] Game random lags

Has this always happened ever since you've had this game? Or only since when?

Does this also affect our similar games CK2 and HOI4?

DXDIAG is a program you run from the Windows search box on the task bar. After running it will open a window and start collecting info with a progress bar in the lower-left corner. When it completes click the 'save all information' button and save it to a file then attach that file here.

Please attach here your Documents/Paradox Interactive/EU4/settings.txt and pdx_settings.txt .
From your Documents/Paradox Interactive/EU4/logs/ folder, attach here system.log , error.log .  

CK3 is a much newer game and not particularly comparable. Does this also affect our similar games CK2 and HOI4?

DXDIAG is a program you run from the Windows search box on the task bar. After running it will open a window and start collecting info with a progress bar in the lower-left corner. When it completes click the 'save all information' button and save it to a file then attach that file here.  

I see no reason for this in those files, I'm sorry.

If you revert to the game version from a week ago 1.31.5 , in the Steam Betas tab for this game, is it better again?  

Okay then, when you said 'recently' in your OP here, when was it that the game last performed okay for you? Do you know what patch version that was?

What we are trying to establish here is whether a version that used to work okay for you is now slow (so the problem has just occurred) or is okay (so the problem may be in a game patch).  

3 weeks ago means it pretty must has to have been 1.31.5 you were on then. IOW that same game version used to run okay for you but now does not ... !

Let's try a full **clean** re-install:

- move any valued save games elsewhere
- "uninstall" in Steam-EU4
- manually delete both the Steam/SteamApps/common/EU4 AND Documents/Paradox Interactive/EU4 folders
- re-install game in Steam, run a Steam Verify when done.
- add EU4.exe to the exceptions list of your antivirus app; ESPECIALLY if you have Windows Defender, add it to the Ransomware "Apps Allowed Through" list.
- start the game with no mods active and test with a new campaign - NOT any existing one

In particular make sure there are no files or folders left under either the Steam EU4 or Documents EU4 locations, before installing again.  

Really, that's a new one on me! I wonder why it picked on just this game, and why just now ...

What AV was that?