So about a week ago 1212AD just stopped working...it would load and then crash on the splash intro screen. I uninstalled the whole game, then reinstalled, and it looks like a medieval wall add-on mod I downloaded (not created by the 1212 team) was the culprit.
There was also a newly released 1212AD models pack ('Models-8') that I did not know about and didn't auto-update through Steam.
So...right before I couldn't load the game, I was getting my arse handed to me as Brabant, by Verona (!!!). Since I have the OCD and am a completionist, I will serve out the rest of my punishment. Once Brabant crashes into an ashy heap I hope to start a long awaited campaign as Wallachia finally (ranked as 'Very Hard' in the campaign description).