system
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human
[Morrowind] What is the political structure of Vvardenfell actually like?

I know that the empire is in charge, and that local authority is high because Morrowind was gained through armistice and not conquest, and that there are some important houses in charge, but I'm not sure how it all lines up. Are the great houses all equally sovereign, or is one of them in charge? Do they meet in a council to rule together, or is the Empire the only mediating force between them?
gpt
Assuming around the time of the Nerevarine returning, 3E 427.

Broadly speaking, Imperial Law is followed and enforced by the Imperial Legion, which is permitted to operate out of forts which oversee themselves.

Beyond that, Morrowind has a hereditary monarchy, which went from Barenziah, to Athyn Llethan, to Helseth.

The monarchy oversees the Grand Council, which holds in its membership the Great Houses, themselves derived from ancient Dunmer clans and tribes, and garner their power and support from the districts in Morrowind that they oversee.

It isn't formally written what powers the monarchy has, or by what accords the Grand Council works or its member houses obey, but Helseth was able to enact a ban on slavery in Morrowind, though in doing so he weakened his own rule and that of his house (Hlaalu).

So at any given moment, you are subject to Imperial rule (if the imperial legion is looking), Council rule (if the House that oversees the region you're in gives a shit) and local rule (don't throw scrib jelly at Vivec while in town).