Game won't Launch [MacOS]

Please delete the ~/Library/Application Support/Paradox Interactive/ folder. To see it go to the Finder, hit command-shift-G (ie Go To) and paste in ~/Library/Application Support/ . Then run the game from the PLAY Button in Steam, to reinstall the launcher.

If that does not get the launcher running, we will need these files from that same folder:

Attach ALL .log files Found here ~/Library/Application Support/Paradox Interactive/launcher-v2/


Meantime, what happens if you run eu4.app directly from Finder?  

If that does not get the launcher running, we will need these files from that same folder:

Attach ALL .log files Found here ~/Library/Application Support/Paradox Interactive/launcher-v2/  

Those logs go back to September last year, so I'm afraid you cannot have done the delete-reinstall process I outlined fully. Please go through it again, doing every step. Thanks!  

Almost certainly you've gone to the wrong Library folder, there are many in MacOS.

If you do exactly this:

To see it go to the Finder, hit command-shift-G (ie Go To) and paste in ~/Library/Application Support/

You'll get there.  

As the launcher runs, that folder simply must be there!

In Finder click on View - Show Path Bar. Then do you that folder as I described; what do you see in the Path Bar now?