Mage States are generally defined as independent or semi-independent territories under the control of mages or Mage Orders. In nations where Mage States reside, they are officially recognized by that sovereign nation, and most are protected either by local mage laws, deities, or the influential Mage Order.
It is within Mage States that mages are afforded more freedom, and they can live reliably and study or practice magic without causing any standing issues with the local populace. Outside of Mage States magic is often feared or hated by commonfolk or others who don't understand magic, so the need for sanctuaries became apparent, and thus various Mage States were formed.
In most cases, Mage States were created between mages who sought similar goals, and wanted to pool together resources and minds to achieve some form of cooperation between mages in practicing and studying magic. In some rare situations a Mage State might have been established by a ruling nation, as a way of containing mages within a set area to more easily govern and control them; as was evident of the Sanctum Magi before it broke free from Valaísian rule and became the Convocation of Mages.
In essence these States are created for the express purpose of acting as refuge and sanctuary for mages, and allow mages (in most States) full or some freedom in governing themselves.
An island magocracy situated in Arganorh, at the center of the world. Controlled by the Convocation of Mages, and it is the seat of power of the Arch Sanctum.
A magocratic city-state in the High Marches. Founded by the Thaven Hand, and it effectively acts as their main city of operations in Norrhan.
The third home of the Sectum Tor. Achantia is a small magocratic nation situated by the coast of the Peacock Sea in Ryumar, and it is currently the center of Sectum Tor authority.
The mage city-state of Candlehold lies in the Arreath Peaks in Avanor. It is home to the Candlehold Order and the Spiral Library; where the largest repository of knowledge in the world is stored and curated.
A safe-haven and sanctuary for illegal mages. Shadowlight is a small island and city-state in the Sea of Darks in Norrhan, where mages considered to be illegal have assumed power, and thwarted attempts at removing them for several decades.
Magehouses are smaller mage sanctuaries, similar to embassies or guild halls. They act as private inns for mage travelers, or as clubs and cafés for mages only; depending on the city or nation, and whether mages are allowed such freedoms there or not. In some cases a Magehouse might be established in secrecy and hidden from local authorities; serving as hideouts for illegal mages.
In nations or states, typically where mages are afforded freedoms (like in magocracies), where a Magehouse is created, it serves mages as a way for them to enjoy luxurious leisure and the company of other mages, without having to mingle with commonfolk and Unawakened. Most Magehouses are established in large, civilized cities, though some rare ones can be found along the roads or hidden away in the wilderness.
Magehouses are ideally private locales meant only for mages, and any non-mage who enters them is promptly kicked out by hired enforcers, though in most cases a Magehouse might employ magical devices or spells that keep outsiders away. Since many mages are typically wealthy or carry valuable items, Magehouses are often the target of thieves, though magic traps will keep most thieves from trying their luck, save for the most foolish or most skilled thieves.