The Night King, the supreme and first White Walker, has existed since the First Men. He was also the supreme commander of the Army of the Dead. The Night King was formerly a mortal man who served as one of the First Men in a lengthy conflict with the Children of the Forest.

The poor man was discovered by a small group of greenseers as the Children were losing the conflict, and they shackled him to a heart tree so they could use him for a terrible purpose. After Leaf, a member of the group, stabbed the captive in the chest with a cursed dragon glass dagger, the captive’s eyes turned blue and he turned into the first of the White Walkers.

Bran Stark is informed by Leaf that the White Walkers originated thousands of years ago as a result of the First Men’s conquest of Westeros, following the destruction of their sacred trees, and slaughter of the Children of the Forest.

The Long Night, however, started as soon as the White Walkers turned on their creators. The War for the Dawn brought an end to the Long Night, but the Night King survived. He and the other members of his race made their way to the Lands of Always Winter, where they hid and rose to legend.

How was the Night King created in ‘Game of Thrones’? How were the White Walkers created?

The Children of the Forest produced the Night King, who lived for nearly 10,000 years, during the Wars of the First Men and the Children of the Forest.

He was taken hostage by the Children of the Forest, who later used a dragon glass blade to stab him and transform him into the first White Walker.