The dwarves of Kage were created in the 1st Age by the Draconic Gods. They were formed from the stone and earth itself as servants for the dragons (along with the orok), but have long since broken the shackles of slavery.
CNote: Attached below is a Summary of Races doc for Kage. It includes racial origins. It is where everything stood at the end of 3e dnd, but I believe not a lot will change - esp with core races (those woven into history of Kage).
The origin of the races and inclusion of list of Guardian Races is interesting.