Just a note: This piece is going to be a stand alone story within Elder Scrolls myth/lore. Only the prologue is very loosely tied to TES4: Oblivion, and maybe in later chapters more references will be made. It's going to take place in Cyrodiil, and might expand into the different countries of Tamriel. Until then, please enjoy, and be constructive in your criticisms.
Prologue-
Storm clouds had gathered earlier that evening, and zero hour was heralded by a steady rain. The guard posted outside of the Kvatch main gate stared solemnly into the murky blackness. He would not be relieved for some hours to come, which weighed heavily on his boredom. Not even the most adamant evil-doer would venture out tonight, or so he thought as the sound of horses approached. The guard drew his sword and approached the source of the noise, when suddenly the rattling chains of the main gate opening commanded his full attention. The captain of the guard, Savlian Matius, casually crossed the threshold and approached the carriage. Three men emerged, one in monk's robes and the others in Akaviri armor. They and Matius exchanged pleasantries and went into the city; minutes later they emerged with the half-naked priest of Akatosh. Matius stood within the city and watched the strangers drag the unruly priest away into the night, and as the carriage departed the gates closed behind them.
The priest grew more and more restless as they traveled, feeling his pleas and protestations were falling upon deaf ears. Finally, the man in robes spoke.
"Please forgive us for being so curt, Martin, but you will soon understand that time is of the essence."
Just as the priest, Martin, was about to speak, his words caught in his throat, "How... how did you know my name?"
The old man smiled, "I have known you since I was your age. My name is Jauffre, and I am the grandmaster of the covert order of the Blades. To my right is Steffan, one of my captains, and to your left is Baurus. He was with your father before he was assassinated."
"That's impossible; my... my father was a farmer. Who are you people really?"
"Your father was the emperor."
It took full seconds for the sentence to process in Martin's brain, but when it did he laughed, "You are certainly gracious captors. Do you humor all of your victims before you do whatever it is you do with them?"
"This is no joke. You are the illegitimate heir of Uriel Septim."
"If I am illegitimate, then, why do you whisk me away in the middle of the night instead of appointing the crown prince to the throne?"
"They were assassinated before the emperor was murdered."
"But... I'm just a priest..."
"Your are a priest of Akatosh," Jauffre quipped, "Do you think that is mere coincidence? As a priest, you should know the importance of the covenant between the Empire and Akatosh. Right now we are without an emperor. The Dragonfires are cold, and the bridge between worlds is in serious jeopardy."
"I don't believe you."
Jauffre nodded to Baurus, who produced from his pack a large jeweled amulet.
"Do you recognize this?" Jauffre asked.
"Yes. It is the Amulet of Kings."
"Indeed it is, and only an heir of the covenant is able to wear it. I'm sure you don't believe me, which is why I now ask you to clasp the amulet around my neck."
Jauffre leant forward and bowed his head, waiting. Martin reluctantly took the amulet from Baurus and clasped it around Jauffre's neck. For a moment the clasp held, however, it took less than a second for the chain to warp and separate, causing the gem to fall to the ground.
"Now then," Jauffre said rising with a slight smirk, "You've seen it for yourself. If you don't mind, I now ask that you place it around your own neck."
Martin retrieved the amulet, "This is absolutely ridiculous. I don't see how..."
Martin's words completely failed him as he not only clasped the amulet, but sat idly by as it remained on his neck. He stammered, and then fainted.
"Grandmaster, are you certain you're taking the right action in crowning Martin?" Steffan asked.
"What choice do we have. Tamriel needs an emperor to remain intact. I can't imagine the turmoil that would arise without an heir of the Dragon Blood. I'm sure, with time, young Martin will grudgingly accept the role he was born into. He may never grow fond of his position, but being a priest, he is kind-hearted enough to understand that his people come first."
They arrived in the Imperial city two days following, Martin being schooled in the ways of the emperor as they traveled. His coronation commenced that day, and that night an Oblivion gate opened near Castle Kvatch. As soon as the first wave of Daedra swarmed upon the city, the gate shut behind them. The Dragonfires had been lit.
Days later a Redguard astrologer met Bothiel in the Arcane University's Orrery.
"I'd like to thank you from coming all the way from Stros M'kai. I thought I had calibrated something incorrectly in the machine. When my equations were proven to be flawless I surveyed the skies and, to my apprehension, saw it for myself."
"I had noticed it too," the Redguard said, "And I came to the same conclusion as you. On the journey here I too looked to the skies and saw. I've studied your lore, and the lore of other nations, but never have I come across anything like this in all of written history, or in my own experience."
What they spoke of happened at the lighting of the Dragonfires. As soon as the basin was ignited, Jone and Jode, the two moons, ceased to orbit in the sky.