Generally known as The Strongholds, The Confederated Strongholds of Northern Hann is a political entity that was created to manage relationships between the three major holdings along the River Still - Stilan, Melange and The Complex. Over time, Rostil and Westland have been added, and the structure tweaked to fit with that of The Hann Empire.
This was my first 'game world' back in the days of AD&D - before it became AD&D II :] The three original states are based on the 1st ed rules for strongholds - Fighters control more land than clerics who control more land that wizards … I still have the original paper based version sitting on top of my book case, the concepts hold, but deities and some specifics have changed, to work with more modern rule sets.