Player characters in this campaign must be of a Non-Evil alignment. The bent towards Law or Chaos is irrelevant for PCs, but their alignments will have an effect on NPC attitudes toward them.
Lawful characters will get along better with members of established organizations and power structures (like the Noble Houses or one of the Autonomous Orders). As well as the common citizenry of population centers.
Chaotic characters will do better outside the cities and among people who prefer a little more fluidity with the rule of law (like among the Freeholds).
Good characters will get along with pretty much everyone on some level, even NPCs of an evil alignment tend to play along when it comes to social interaction unless its an overtly evil society (like the Goblin Hold, or one of the Syryllian Duchies).
Neutral characters will find that their lack of commitment, one way or the other, can be met with some level of uncertainty or distrust. They must be very careful walking the fine line neutrality demands.