In its sixth season, Game of Thrones has been answering a lot of longstanding questions, even as it continues to tease at others. In Season 6, Episode 5, "The Door," fans saw the origin and creation of the White Walkers, solving one mystery but leaving a lot of others still open to be explored down the line. While the reveal that the Children of the Forest created the Walkers provides some resolution, it also leaves behind a lot that's unanswered. In particular, there is still a lot left unknown about the leader of the White Walkers. Who was the Night King on Game of Thrones?
The A Song Of Ice And Fire books provide some legends surrounding the Night's King and where he came from, but there's no way to know yet just how true those stories are. In "The Door," the very first Walker created by the Children is the Night's King. The viewers see a man tied to a godswood tree as one of the Children pushes obsidian into his chest, then a closeup of his eyes turning an icy Walker blue. While it explains a lot about where the Walkers came from and what their original purpose was (to protect the Children from the First Men), it also doesn't tell fans anything about who the Night King was before transforming.
According to stories told in the book series about the Night's King, he was actually a member of the Night's Watch. He lived thousands of years ago and served as Lord Commander shortly after the creation of the Wall; he was only the thirteenth Lord Commander, and considering Jon Snow was the nine hundred and ninety-eighth, that's a long time ago. He fell in love with a mysterious woman who had ice-cold skin that was "as white as the moon" and also had "eyes like blue stars," which sounds a lot like a description of a White Walker.
He married her and brought her back to the Night's Watch stronghold, Nightfort, where he ruled with her as self-declared king for over a decade. It was a violent, terrifying rule, and he allegedly made sacrifices to the White Walkers in that time. He was only overthrown when the King in the North and the King Beyond the Wall joined forces to take him down. In the books, the story is told to Bran by Old Nan, who also claims the Night's King was brother to the King in the North, making him a Stark.
This creates some interesting connections between the White Walkers and the Starks, and also contradicts some of the information seen on the show. The Wall was created to keep the Walkers and the wildlings out of Westeros, so going by that story, the White Walkers already existed by the time the Night's King entered the picture. If he was indeed the first Walker, then that throws out the entire legend about him taking a Walker for a bride. Of course, legends are legends for a reason; they don't always have a whole lot of truth to them.
Still, the Night's King may have a connection to the Starks even without the legend being true. During the battle of Hardhome he was eyeballing Jon Snow pretty intensely, and he was able to see and touch Bran in a vision. Could the Night's King be an ancestor of the Starks?
It would be pretty cool if he was, and it would also bring things full circle in a way the series often likes to do. If fans have learned anything from Bran's visions, it's that they often provide just as many questions as they answer, so perhaps more information about the Night's King will be revealed down the line.