Aasimar

History
Despite the common myths of the ancestry of the aasimar, the truth is far more interesting. Several thousands of years ago, before the material plane had mortal creatures on it, other beings across the many other planes used to wage massive wars against each other for power and resources. Particularly the the demons, devils and celestials fought the most and caused the most destruction. The wiser amoungst all three knew that these wars of attrition could not last forever, they also knew that they needed neutral ground in order to meet and discuss peace treaties. One being from each the devils, demons, and celestials came together and poured their life force into birthing a new creature, one of pure neutrality. the first two group of aasimar.

These first aasimar were instructed to build a location for the leaders of these other planes to meet and discuss terms of peace. The first aasimar quickly set forth and built into the side of a mountain a great kingdom in which to house future generations and to be the meeting halls they needed. Jump ahead several generation and the aasimar have become a fierce society with strict laws, they have found a way to harness neutrality as a weapon and hurt those who who bent to far into good or evil. They also have brought several decades of peace amoungst the the outer planes, which has never been known to happen.

Unfortunately though, one demon took an unhealthy interest in the power the aasimar had consolidated and became Jealous. Lillith, and very powerful demon lord, broke every treaty they had signed and invaded the assimar kingdom. The aasimar had never considered this a possibility so she rolled though their forces within a day. The surviving aasimar that managed to escape became the the aasimar we know today. Lillith however have punished by everyone else for breaking the treaties and they used powerful magic to lock her to the kingdom, and she was forced to live the rest of her days in a crumbling ruin.

The Reclaimed Aasimar
If an aasimar has proven, to higher beings that originally created their race, that they embody the values of their ancestors they can ascend to being a reclaimed aasimar