Ruling directly over these two provinces is the god Almalexia. When you land in Stonefalls, there are a couple of quests where you speak to vestiges of Vivec, Sotha Sil, and Almalexia, but during the questline that starts in Mournhold, you can actually speak to Almalexia herself in person.
This got me thinking about what exactly makes a “god” in Elder Scrolls. It’s widely accepted that the Aedra like Akatosh and Mara are gods because they were instrumental in the creation of the nirn, and historically, the Dunmer worshiped Daedric Princes like Azura, even though most of them worship the Tribunal now. But what makes the Tribunal (Vivec, Almalexia, and Sotha Sil) gods? What makes someone a god of Nirn in the first place?