Tiber Septim is a very important person as lore goes. He was a war hero, the first emperor of the Septim Dynasty, and he even became a god. So with how much he has to do with almost everything, I decided to make him my post.
Note: This took a very long time to make because I had to read the whole page at least once. I read it completely once, and went from beginning to end summarizing what I thought was important. It took time out of my day to do this, when I'm supposed to be doing homework and and studying. I did this so y'all can learn some stuff about lore. I hope you enjoy.
The following is also the agreed theory of his life. It's mostly accurate of what happened, but some isn't, necessarily. It's unknown all of what happened.
Tiber Septim was born known as Talos in Atmora, which is a continent north of Tamriel, across the Sea of Ghosts. Atmora was home to Atmorans*, which were a race of men in the Merethic Era. Talos had a brother named Agnorith.
As a child, he was raised in Skyrim. He was taught to fight and learned about war. After a while, he became known as General Talos of the Colovian Estates, and he was under the order of the current king and soon to be emperor Cuhlecain.
General Talos went against the armies of Skyrim and High Rock, who were against Cuhlecain. At Sancre Tor in the Jerall Mountains, in Cyrodil. The army of Skyrim surrendered to Talos after they saw the power of the thu'um and knew that he had the blood of a dragon. They also knew that he was supposed to be emperor.
In about a year, Cuhlecain. and General Talos had taken over western Cyrodil. Their army was surrounded by a large army of battlemages, and the battlemages were destroyed. In 2E 854, they conquered the Imperial City, when they did that they were in control of all Cyrodil.
In the year that they conquered the Imperial City, a High Rock nightblade assassinated Cuhlecain and slit Talos's throat. The nightblade also burned the palace. Talos managed to survive the attack, but he could no longer shout, just whisper**.
Talos got around, he was a bit of a player, and he had an affair with Barenziah of Morrowind. He got her pregnant, and he decided to abort the unborn child that way there wouldn't be any conflict with his real son.
In the following years, Talos had taken over every single human kingdom, which included Hammerfell. After Hammerfell, he went to Morrowind to take over. He did that through a treaty, and went to the Summerset Isles and succeeded there. He had done a conquest of Cyrodil.
In the early Third Era, Talos died. After his death, most believe that he became a god. He united Tamriel for the first time in history. But during the great war between the Empire and the Aldmeri Dominion, the peace was agreed with the fact that Talos wasn't divine. The Empire wasn't originally stopping Talos worship, but the Dominion started enforcing it by destroying statues and temples. The Stormcloaks didn't allow this to happen in their towns.
The Septim bloodline went extinct with the death of Martin Septim.
*Talos wasn't an Atmoran, his race is unknown. It is said he was a mixture of man and mer, which would leave Breton, but it is still unknown.
**This isn't on the wiki, but from my own knowledge. If you loose your vocal cords, you can't talk or yell, but you can whisper. Whispering doesn't use vocal cords.