"Aasimar are humanoids with an angelic spark in their souls, which grants them supernatural power. They come in 3 variants and they must be part of one of Faurun's factions to be Adventurer's League compliant (VGM p104)."
Aasimar are an uncommon race and are the polar opposite of the Tiefling, essentially a mix of human and celestial. They come in three types, Protector, Scourge and Fallen, on Iyvis. Protector and Scourge Aasimar are rare in this world, but not unheard of, while Fallen Aasimar are almost non-existent.
They don't claim any major areas of land as a race and tend to be found in larger cities throughout the world mixed in amongst more common races. However there are a handful of cities across the world which are mostly made up of Aasimar, but these generally fall under the control of other races.
Aasimar are well liked by most other races, however they have a deep distrust for Tieflings, sparking the war between them and Humans, but are generally opposed to the enslavement of almost the entire race.