Knight at Arms
Actually no, I'm pretty sure that some lords are set in stone. Meriga is always quarrelsome and I think Atis (lord of Bariyye) is as well, Clais/Plais from Swadia are always pitiless/debauched iirc. Most lords change every game, but some are decided for some reason. Likely so that the player is forced to play nice to them if he wants an enterprise in their town. Also in order to make sure that a game never has too many good or bad lords, I suppose. Which means there are probably lords that are always good, I think Delinard is one but not entirely sure about him.