The first colonists to settle Umayma were a reconnaisance party from the moons, where they had endured a long exile with tens of thousands of others as the world was made habitable. They were the test party, selected for strength, speed, endurance, and immunity to toxins.
Those first families settled in what is now Nasheen, the least toxic part of Umayma. As the advanced party, they spent decades assisting the magicians in tailoring the world for habitation. When the other colonists began falling from the sky unannounced, the first families clung to their existing homes and status, forcing others to toil and scrabble with limited resources.
The Caliphate was instituted by one of the most powerful magicians in the world whose influence had led the group of magicians first assembled to make Umayma habitable. Members of the Families were in charge of most governance, and served as intimate advisors to the Caliph. When they finally overthrew the Caliph and instituted their own monarch, they were able to do so easily because they were already so embedded in the country's everyday governance. Few regular Nasheenians have much dealing with the First Families. They rule Nasheen high up on organically sealed hills and compounds with restricted access. Even their servants, gardeners, and drivers are heavily screened and scrutinized.