In "Beyond the Wall," Jon Snow and his group figured out that when a White Walker is killed, the wights it controls also dies. They discussed that all they had to do was kill the Night King – but it’s not as easy as it sounds.
The Night King controls so many wights, and now a dragon too, they’re gonna have to get through all that to kill him. While his powers were shown throughout the series, his identity still remains a mystery, and there are differences in the books and the show.
A Song of Ice and Fire
The Night King in the books is considered to be more of a myth and a legend, like Azor Ahai.
He lived in the Age of Heroes – which was 8000 years before the events in “A Game of Thrones.” The Night King was the 13th Lord Commander of the Night’s Watch (and Jon is the 998th).
According to legend, the former Lord Commander went beyond the wall and met a beautiful woman. The mysterious woman was described to have white skin and blue eyes, and that her touch could freeze anything. They consummated their love and took up residence in the Nightfort. They stayed there for 13 years, he proclaimed himself king, and practiced black magic and made sacrifices to the White Walkers.
His practice ended when the King in the North (Brandon “the Breaker” Stark) and the King Beyond the Wall (Joramun) fought together against him.
The stories and details about the Night King in the books come from the Bran’s memories and the stories of Old Nan.
'Game of Thrones'
In the show, the story of the White Walkers and the Night King were shown through one of Bran’s visions in “The Door” (S06E05). The Children of the Forest pressed a dragonglass dagger into the heart of a captured First Man.
The man became the first White Walker and the Night King.
Leaf explained that they created the White Walkers to protect themselves from the First Men. The White Walkers somehow broke free from the control of the Children and became a threat to all living. The Children and the First Men worked together to defeat the White Walkers.
Similar to the books, the Wall was built after the White Walkers were defeated and the Night’s Watch was formed.
Theories
There are several theories with regards to the Night King’s true identity before he became the what he is. According to Old Nan, there is a rumor that the Night King is a family member from House Umber or House Bolton and even House Stark. There are also rumors that the Night King is Brandon Stark’s brother.
One popular theory is from the Reddit user, turm0il26. He theorized that Bran Stark is the Night King. The theory suggests that Bran is going through time to stop the White Walkers from becoming a threat. Bran eventually wraged into the First Man that was captured by the Children.
When the dragonglass was pressed into him, he became trapped in the body and transformed into the monster he was hoping to defeat.
There is also an explanation that the Night King could be a metaphor for death. According to D.B. Weiss’ interview with Deadline, he explained that evil is when someone chooses between bad and good. He wasn’t given a choice; he was just created that way – a force of destruction. Just like death, the Night King is coming for everyone.
