The Undane alliance was composed of a loosely organized set of ruling councils called cabals. Each cabal had a secret underground fortress from which it ruled its territory. These cabals were always made up of halflings, and tieflings, all other races in Undane territory were subservient.
The Undane were master magic craftsmen and were best known for their ability to make constructs. Armies of flesh gollems helped the Undane maintain control for hundreds of years.
All humans living in Undane lands were born as slaves to the cabals, and were refered to as greevties or untouchable. It was an ironic twist that when the humans finally rebelled and established there own kingdom they would name it Greevties, perhaps to remind themselves of where they came from.
Many believe all the Teiflings have been wiped out, none have been scene since the fall of the Undane, but halfings can still be found, some even living in the Empire. However weather these halflings had any connection to the cabals or not they are mistrusted and shunned in society.