The Dwarven Cleasing
9990B.P.
Some of the Azer and Duergar dwarves defy their brothers and sisters and start to worship the Forge Pantheon. A cival war erupts between the planes with the Gods intervening, spiriting away their worshippers. The Azer dwarves were moved to the hills and deserts, turing into the Hill Dwarves, while the Duergar were spirited to the plains and mountains, turning into the Mountain Dwarves.