Magic is Everything
The Magocratic society of Huricrest is structured into a caste system, with mobility limited to your ability to use magic. Normal citizens, with little to no magical power, are the second lowest caste and this is the only caste that you can be born into. To be recognized as a Mage, a Citizen may petition the Council for a spot in the bi-annual reviews. They will then be judged on their ability to use magic. Promotion from Mage to Councilor is a political decision, with most Councilors having control over vast swaths of Huricrestian territory. The Councilors elect an Elder to chair the Council. The appointments to the Council and to Elder are made for life.
Slavery is legal within Huricrest, and slaves form the lowest caste. Most slaves are serving on a contractual basis, often paying off a debt through service. While slaves enjoy the right to not be killed or maimed, they are also expressly forbidden from casting spells.
The politics of Huricrest are cut-throat; sometimes literally. Given the lifetime appointment to the Council, open seats are fiercely contended by Mages not already on the Council. Assassination, often using hired swords from the Freecity of Havia, is the most common method for advancement.