He experiences a flood of images from the past, present, and future, many of which he was not physically present for. The Night King first appears in a vision that Bran Stark has when Bran communes with a Weirwood Heart tree.

The Night King approaches an altar-like ice formation where Craster's son is placed. The Night King is a legendary figure, known by name among, at least, some noble houses in the North. Though the Long Night ended upon the First Men and Children's victory in the War for the Dawn, the Night King survived and retreated with the rest of his kind to the Lands of Always Winter, where they hid and faded into legend. However, the White Walkers soon turned on their creators and began what was known as the Long Night. Thousands of years later, Leaf explains to Bran Stark that her people created the White Walkers to defend themselves when Westeros was invaded by the First Men, who were cutting their sacred trees down and slaughtering the Children of the Forest. Leaf, who was among the group, pressed a cursed dragonglass dagger into the captive's chest, causing his eyes to turn blue and turning him into the first of the White Walkers. As the Children were losing the war, a small group of greenseers captured the unfortunate man and bound him to a heart tree to be used for a terrible purpose. The Night King was once a mortal man, one of the First Men who waged a lengthy war with the Children of the Forest. Leaf turns a First Man into the Night King.

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