It should surprise no Game of Thrones viewer that the ultimate antagonist of the series would come from North of the Wall. Ever since the first scenes of the show, the White Walkers have been making blood run cold (quite literally). Ultimately, it doesn't seem to matter much who "wins" the game now that winter is here and an army of icy zombies is heading south/
Leading the charge is the Night King, the head White Walker leading an army of glowing blue eyes and flanked by countless undead wights. And now he has a dragon, since he managed to kill and resurrect Viserion. Other than that, we know very little about the Night King. Where did he come from and was he once human? And could he be... Bran Stark? Fans have several theories about the Night King's identity. Let's explore them in greater depth.
Theory 1: Bran is the Night King
This is definitely the flashiest of theories, and it appears to have been sparked by a striking resemblance some viewers saw between The Night King and a certain three-eyed raven. Another compounding factor comes from S6, E9, "Hold the Door," in which Bran wargs into a young Hodor (then known as Wylis) during a greensight vision of the past. If Bran can essentially travel anywhere in time and enter into any body he likes, it seems technically possible he is the Night King.
The prevailing theory is that, in his constant travels back in time, to try to save humanity, he's basically created a series of time loops that sealed their fate. And it runs deeeeep. We've now seen evidence of Bran manipulating events in history at least twice and possibly more.
For one, he caused a young Wylis to witness his own death in the future, which is what led him to be unable to say anything other than "Hodor" a truncation of the phrase "Hold the door," which Meera shouted over and over as the White Walkers closed in.
We also saw Ned react to Bran yelling, "Father!" at the Tower of Joy fight with Arthur Dayne. And it's possible we've heard of a third example. Some people who adhere to this theory think The Mad King may also have had an encounter with Bran trying to use his greensight to end the White Walkers siege. Perhaps the Mad King wasn't so mad after all and the voice he heard saying "Burn them all" was Bran trying to get King Aerys Targaryen to use his dragons to take out the White Walkers in the North.
Instead of working the way Bran hoped, the encounter turned Aerys insane and made him kill his own people.
The theory also suggests Bran goes as far back in time as the building of the Wall by another Bran: Bran the Builder. Taking the theory even farther back in time, he might try to go back to when the Children of the Forest made the White Walkers. Bran inhabits the body of the man they stabbed in the heart with dragonglass, only to get trapped there and giving the Night King his ability to warg, see everything, and raise the dead.
There's definitely evidence the Night King has greensight. He seemed very very prepared for battle with Jon Snow's men, and was even able to score himself a dragon. This is the most developed Night King Theory, but there are others, like...
Theory 2: The Night King is Azor Ahai
Azor Ahai is the Prince That Was Promised to defeat the darkness. It's been assumed this whole time that the "darkness" refers to the White Walker army and the winter, but what if men are the darkness?
What if, according to legend, mankind is the scourge that must be defeated by Azor Ahai? That would seem to position the Night King as the prince of legend. In this fan theory, Viserion is Lightbringer, rather than a sword. It's also worth noting that Azor Ahai has never been mentioned on the show, though Melisandre has referred to The Prince That Was Promised several times.
Theory 3: The Night King is Bran the Builder
This theory suggests that the elder Bran fancied himself Azor Ahai and tried to fulfill the prophecy by burying his sword in his wife, Neesa Neesa, to reforge it as Lightbringer. Instead. she just dies, and he goes to the Children of the Forest to get help resurrecting his wife. Instead. they stab him in the heart with dragonglass and he becomes the first White Walker.
The big problem with this theory is that the Azor Ahai story has its origins in Essos and a lot of fans are conflating it with a story Old Nan told Bran about the Long Night. Still, it's an interesting theory!
Theory 4: The Night King is just some guy.
Look, we get it. With a show as complicated and sprawling as this, it's easy to go looking for convoluted theories where things are actually very straightforward. But maybe we already know who the Night King is. Bran saw it himself when he and the OG Three-Eyed Raven saw the Children of the Forest make him.
He's just the first White Walker, made when some unlucky dude happened upon the Children when they decided they needed a weapon to help them fight the First Men.