Following the defeat of the Dwemer, the Tools of Kagrenac the Master Craftsman fell into the hands of the Chimer, ruled at the time by Lord Indoril Nerevar, to whom fell the burden of the decision as to what to do with them. Dagoth himself, at first, urged for their immediate destruction, either of the Tools or the Heart itself: Nerevar, taking this as a sign of Dagoth's trustworthiness, opted to leave Dagoth behind to guard them while consulting his councillors, the Tribunal of Vivec, Almalexia and Sotha Sil (and the Dunmer's Daedric patrons, Azura and Boethiah) on the subject.
But, when Nerevar returned with the councillors' decision - which was, indeed, to destroy and not use the Tools - Dagoth refused to give them up, holding that he had been entrusted to guard them. He had, in the absence of Nerevar, been tempted to experiment with the Tools on the Heart, and somehow managed to steal some of its divine essence and the power of immortality. He now called himself Dagoth Ur, and was forever after known by that name. Nerevar and Dagoth Ur came to blows: Dagoth-Ur was defeated, driven off and thought to have been destroyed (along with most of his House who supported him: the remainder were absorbed by the other Great Houses, and House Dagoth ceased to exist as an entity), but Nerevar was seriously wounded as well. He was to die shortly afterwards, possibly having been killed by the Tribunal, who did not destroy the Tools or the Heart, but instead stole divine powers from it for themselves. Thus, Dagoth Ur's connection to the Heart was not destroyed, and he remained alive and immortal, albeit bodiless.
But, when Nerevar returned with the councillors' decision - which was, indeed, to destroy and not use the Tools - Dagoth refused to give them up, holding that he had been entrusted to guard them. He had, in the absence of Nerevar, been tempted to experiment with the Tools on the Heart, and somehow managed to steal some of its divine essence and the power of immortality. He now called himself Dagoth Ur, and was forever after known by that name. Nerevar and Dagoth Ur came to blows: Dagoth-Ur was defeated, driven off and thought to have been destroyed (along with most of his House who supported him: the remainder were absorbed by the other Great Houses, and House Dagoth ceased to exist as an entity), but Nerevar was seriously wounded as well. He was to die shortly afterwards, possibly having been killed by the Tribunal, who did not destroy the Tools or the Heart, but instead stole divine powers from it for themselves. Thus, Dagoth Ur's connection to the Heart was not destroyed, and he remained alive and immortal, albeit bodiless.
How long was it between the Nerevar's meeting with his council and trusting Ur with the tools? Could it have been long enough for Ur to tap into the power so rapidly?
My other question is: What IS Dagoth Ur? Dunmer? Chimer? Altmer?
I also have more when the chances arise.
Edit: I'd also like to note that my Lore Knowledge is Novice. I'm not to far into the Lore. Yet.