Factions

Setting the Stage
In the samurai movie Yojimbo (A Fistful of Dollars, or Last Man Standing, they're all the same story) the main character comes into a town and finds two factions at war with each other. That's all that's needed for the set-up and action adventure is the result. Any adventure can be added to through the use of factions. Conflict inside the game setting can be exciting. And there is no real risk of injury or loss because "it's just a game". Any loss that may occur is inside the game world and only affects an imaginary "character" of course. Conflict can produce "winners" and "losers" inside a hobby that is generally non-competitive. Conflict causes the player to think, strategize, expend resources and roll dice. Factions lead to conflict.
In my campaign there is an ongoing (30+ years) war between elves and men. In addition to making it interesting when someone decides to play an elf PC, the war gives me two powerful factions between which to create constant conflict. The existence of factions in the milieu allows for many possible plot lines to play out. It is not hard when reading a book or comic, or watching TV or a movie to see how the conflict there-in could be adapted to the White Box campaign. I hesitate to use the word plot because I generally like to avoid plotting out story for the PCs. I find it much more rewarding to present a situation (usually more than one) and see where the PCs go with it. Any story that comes out of this style of game play is as much theirs as mine and entertains us all.
Ideally I think factions should exist at every level of society from small rivalries between neighboring shopkeepers to wars between player races and at every level in between. The competing factions give the players opportunity to roleplay and the PCs can react any way they choose. They can ignore the whole thing, as PCs often ignore adventure hooks, opportunities and even rumors of treasure. Or they may choose to get involved.  They may help one faction or the other or alternate back-and-forth between both (as in the movies). They may even decide to join a faction or two. Such membership comes with ready-made friends and ready-made enemies. Lots of fertile ground for adventure!
Law, Chaos and Neutral alignment can be seen as three factions in conflict with each other or at least two in conflict and one that is, well, "neutral". Each alignment faction has it's membership races as outlined in the LBBs and the conflict between those factions is presumably why orcs and other members of Chaos are generally hostile to men of Law. Not everything in the campaign need revolve around alignment, however, and you may find that the inclusion of additional factions makes the action at your gaming table that much more fun for everyone. In the meantime, if you haven't seen any of the three movies listed above, you might want to check one out.