In fact, I have incorporated B2: the Keep on the Borderlands into Kaelaross as Castellan Keep, the eastmost outpost of Teiglin in its borderlands.BackgroundThe Realm of Mankind is narrow and constricted. Always the forces of Chaos press upon its borders, seeking to enslave its population, rape its riches and steal its treasures. If it were not for a stout few, many in the Realm would indeed fall prey to the evil that surrounds them. Yet, there are always certain exceptional and brave members of humanity, as well as similar individuals among its allies - dwarves, elves and halflings - who rise above the common level and join battle to stave off the darkness which would otherwise overwhelm the land. Bold adventurers from the Realm set off for the Borderlands to seek their fortune. It is these adventurers who, providing they survive the challenge, carry the battle to the enemy. Such adventurers meet the forces of Chaos in a testing ground where only the fittest will return to tell their tale. Here, these individuals will become skilled in their profession, be it fighter or magic-user, cleric or thief. They will be tried in the fire of combat, those who return hardened and more fit. True, some few who do survive the process will turn from Law and good and serve the masters of Chaos, but most will remain faithful and ready to fight Chaos wherever it threatens to infect the Realm.
There was a trend in 2nd Edition AD&D to move away from simple, hack-and-slash settings to much more complex, intelligent and subtle settings, where civilization was the norm, and savage, chaotic realms were few and far-between. The Forgotten Realms springs to mind, as does Birthright. Although interesting and good in its own way, it was not quite what I was looking for.
I admit I have not played any 4th Edition D&D, but I can still borrow stuff from it. The most interesting bit about 4th Edition was not in the rulebooks, but a posting during its design and development by Richard Baker about the Points of Light concept for the default setting. This post harkened right back to the background to the Keep on the Borderlands and explained a number of things I had intuitively felt but not said out loud.
Having said that, I think that Kaelaross is actually toned down from Rich Baker's Points of Light, and things are not quite as harsh as he imagines. There are areas that are grey rather than completely dark - much of the current Kingdom of Teiglin is relatively safe (although in D&D that is not reassuring - almost any wilderness is relatively safe compared to some of the realms of chaos where red dragons dominate tribes of orcs and powerful wizards casually disintegrate passers-by).
Nonetheless, when I created Kaelaross, I wanted a reason for large areas to be overrun by Chaos, and for the realms of men to have collapsed or at least retreated, leaving lots of ruined cities. Hence the Wars between the Empires and the Summoning of Bhael. The perfect recipe for a D&D sandbox campaign? Not for everyone, but it was what I wanted, and I'm still happy with it.