Erudites were originally Qeynosian scholars who chose to separate themselves from the rest of their people. They emigrated from Qeynos to the continent of Odus, and built their city: Erudin.
The necromantic arts were banned in Erudin; the High Council feared what necromancy represented. Eventually, one faction led by Miragul wanted to pursue the forbidden arts and split off from the other Erudites in a violent schism. In the ensuing war, violent magics were unleashed that sundered the fabric of Odus. A large magical blast in Toxxulia Forest, blasted a large tract of land and several Kerrans to Luclin, one of Norrath's two moons. These Kerrans eventually became physically stronger and larger, evolving into the Vah Shir.
After everything had settled, there were two clearly separate factions. Good Erudites -- led by those who worship Quellious -- stayed in Erudin. The faction led by Miragul founded the city of Paineel. There were subjects that even the Heretics of Paineel stigmatized; eventually Miragul abandoned his city, and traveled to the frozen north in search of knowledge.
The hunting grounds of Toxxulia Forest are readily accessible to members of both factions, although the Heretics of Paineel do have their own pseudo-private newbie yard as well.
"Good" Erudites begin their journies in the city of Erudin. They can become clerics, enchanters, magicians, paladins, or wizards. They have the option of following the dieties Prexus, Quellious, or remaining agnostic. "Evil" Erudites start in Paineel, and can become clerics, necromancers, or shadow knights. As all of their magical powers are either holy or unholy in nature, the source of the power is granted by worshiping Cazic-Thule, the god of fear and creator of the trolls and Iksars.