4th Era, 12 - 15

Red Mountain erupts; Vvardenfell Destroyed
In Vivec's absence, the Ministry of Truth becomes unstable. Vuhon creates an Ingenium that uses at first dozens of dying souls, then a small number of living ones to stabilize the rock. The soul of Sul's wife Ilzheven was among them. In a fight to free her, the Ingenium is destroyed and the rock crashes into the city of Vivec with all the energy it originally had. The impact causes Red Mountain to erupt and destroys the entire island of Vvardenfell, as well as causing massive destruction to the rest of the province.

The Empire Collapses
Black Marsh secedes from the Empire; it is soon followed by Elsweyr. Shortly afterwards, the Argonians invade southern Morrowind after the eruption of Red Mountain.

Dunmer Relocation to Solstheim
The survivors of Morrowind retreat to Solstheim. Nord settlers are pushed out from the island, into the North Sea in an event known as "The Drowning". The Imperial ruins of Fort Frostmoth become the main entry point to the new Dunmer land.

4th Era, 25

Dunmer Annex Solstheim
In an act of defiance to the Empire, and taking advantage of the Thalmor uprising, the new Dunmer tribunal (consisting of the combined forces of Houses Redoran, Hlaalu and Telvanni) claim Solstheim as the new Dunmer homeland. Relations between the Dunmer and Nords worsen.

New Vivec is Erected
The Northern Skaal village is reconstructed as a large Necropolis. Former Telvanni mages take up residence as 'Tomb Guards'. The Tribunal hold council in New Vivec for the first time.

4th Era, 43 - 44

Flooding of Solstheim
In light of Umbriel's attack on Morrowind, the Mortrag Glacier melts - flooding most of Solstheim. The area near Thirsk becomes a large river. The Raven Rock colony is re-established as the major trading settlement, Vineward.

Completion of Major Towns
The five major towns are completed, after the annexation of the Island. Treaties with the Argonians regain friendship between the two folk. Emissaries from Skyrim and Cyrodiil assist in the creation of the new Dunmer Tribunal. Talks commence regarding return to the Empire.

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Most of the above is done under facts gathered through the TES games, and general lore. Will continue to expand as more is unlocked.