Board Thread:Lore Discussion/@comment-86.176.138.119-20170324162657/@comment-86.176.138.119-20170324182046

I'll answer why first. The Dwemer left the Summerset Isles and the Altmer in the Merethic Era (along with 7 other elf races). After travelling for many years the dwemer settled in the regions of Skyrim,Solsthiem and Morrowind (The farthest North and East provinces of Tamriel). The Dwemer, true to their name of deep elves prefered to live underground despite most magic originating from the sun and stars/the portals to aetherius.

The dwemer used a special type of magic called tonal magic, which is comparable to the Thu'um of Nords and the Sword Singing of Redguards. The masters of this art were the tonal architects, who created the cities by clearing tunnels of rock and decorating them. It would seem that it was much easier for the Dwemer to build flat walls and sharp corners than arcs and curves but that is just from analysis of their architecture. The Dwemer also had skin which was a deeper shade of gold than the Altmer and beards were very fashionable in Dwemer culture.

Their language, dwemeris is comparable to falmeris and ayleidoon (likely the work of lazy developers) although the letters appear to be straighter and with less curves than ayleidoon and simpler than falmeris.

The Dwemer built strongholds across the land and when the daedra worshipping Chimer settled in Morrowind, tensions over territory and food grew, small skirmishes broke out but there was never any major conflict. Some time later a chimer hero called the Nerevar (who was blessed by Azura) brought peace to the land. Despite being a warrior at heart, the Nerevar was also hugely skilled at diplomacy and the art of persuasion through negotiation. The Nerevar used his close relationship with the king of the Dwemer in Morrowind, Dumach to obtain a truce between the two races, unfortunately this would not last.

While expanding the citadel of the Morrowind Dwemer, Red Mountain the Dwemer found the Heart of Lorkan, the literal heart of the dead god Lorkan, which was fired from Auriel's bow into the sky after it was ripped out by Trinimach in the Dawn Era. This artefact was unrivalled in power, surpassing even the Daedric artefacts. Kagrenac, the tonal architech of Red Mountain and his peers examined the heart taking great care, as the simple act of touching the heart would instantly kill any mortal, even touching it with an object would result in a catastrophic accident. Kagrenac created two tools, Keening and Sunder, which alone could touch the heart of Lorkan. The tools, however would weaken anyone who used them to the point of collapse, the gauntlets, Wraithguard were used to counter this.

The Chimer found out about the Dwemer's (in their eyes) sacrilege and by decision of the First Council (The Nerevar, Vivec, Almalexia and Sotho Sil) declared war on the Dwemer. This was to be the War of the First Council. The Dwemer were already weakened by wars with the Nords, the Falmer and the Aetherium Wars. The war was long and bloody but eventually, at the Battle of Red Mountain, the war ended. The Nerevar sent a large force to the front of the stronghold to create a distraction while he and a select few entered (via a secret passage) the room in which the Heart was being held. Dumach and a small Dwemer force fought of the Chimer while Kagrenac worked anxiously on the Heart. Nerevar and his group were forced to kill Dumach and the other Dwemer but The Nerevar was mortally wounded.

Kagrenac finished his work on the Heart just before a Chimer blade was thrust in his back. He disappeared mere miliseconds before the sword pierced his skin. He had disappeared without a trace. Later they would find that every other Dwemer had disappeaerd at the same moment. The Heart later drove Dagoth Ur mad and was used by Sotho Sil, Vivec and Almalexia, giving them godly powers which was seen as blasphemy by Azura who changed the fair-skinned Chimer into the grey-skinned Dunmer which led to the newly made demigods taking over Morrowind and naming themselves the Tribunal which led to events of The Elder Scrolls 3 - Morrowind.

It should be known that the splinter group of Dwemer who moved to Hammerfell because of disgreements with Dumach also disappeared. Also only one Dwemer is known to have stayed on Nirn. Yagrum Bagarn is a Dwemer with the Corprus disease under the care of Telvanni wizard Divarth Fyr. Yagrum was in the Oblivion realm of Apocrypha at the time, you can meet him in Morrowind. Falion from Morthal in Skyrim says that he has seen a Dwemer while walking the planes of Oblivion but he could be lying, he makes other claims that are similarly unbelievable and his stats aren't stellar although he can cure vampirism through a daedric ritual.

Simply put, Lorkan's Heart made the Dwemer disappear.