Game of Thrones tends to be a faithful adaptation of George R. R. Martin's A Song of Ice and Fire. When it does deviate, it usually does so to suit the medium and veers back to the established narrative as quickly as possible. The show features a few changes that are significant and inexplicable. Perhaps the best example is the Night's King, a character Weiss and Benioff barely mention but do borrow from.
The Night King was perhaps the most significant invention of Game of Thrones' adaptation. In the books, the White Walkers have no known leadership structure. This might be owed to the well-publicized switch between adaptation and invention that began around the end of season five and continued over the following few outings. The Night King, a universal antagonist that brings disparate enemies together to stave off extinction, is a bit too simple for George R. R. Martin. Here, it's worth examining the character whose name is a letter off from the show's villain.
Who was the Night's King?
The shortest answer is that no one knows who the Night's King was. He's a figure of legend from the Age of Heroes. That era, between the peace treaty between the First Men and Westeros's indigenous species and the coming of the Andals, is shrouded in mystery. Neither the First Men nor the Children of the Forest possessed a written language, so records were kept in song and spoken traditions. The headline event in the Age of Heroes was the Long Night, the sudden attack by endless armies of undead White Walkers who threatened to wipe out humanity. To defeat the White Walkers, the First Men formed the Night's Watch. The First Men and indigenous species worked together to defeat the winter, winning the War for the Dawn and driving the Others to the far north. To maintain peace, Bran the Builder entreated giants or nature sorcerers to build a gargantuan Wall. The Night's Watch remained to guard, repair, and protect the Wall for 8,000 years. They elect a leader known as the Lord Commander of the Night's Watch. The Thirteenth Lord Commander of the Night's Watch became known as the Night's King.
What did the Night's King do?
The Night's King was celebrated for his bravery and martial skills, virtues that likely helped him win the position of Lord Commander. The Wall was relatively new when he took the job. His backstory varies based on who tells it. He may have been of House Bolton, or Woodfoot, or Umber. Some believe he was Brandon the Breaker's brother, an early member of House Stark. No matter how he found himself taking the black, his life changed when he spotted a woman from beyond the Wall. He was struck with the ethereal beauty of a woman known to history as the Corpse Queen. Her skin matched the driven snow, but her eyes shone with piercing blue light. The Night's King fell madly in love with this wandering undead woman. He ran her down, caught her, and immediately consummated their strange relationship. In doing so, he gave her his soul, binding himself to her forever. The Night's King brought the Corpse Queen to the Nightfort, the first castle given to the Night's Watch, and ruled it as his own. Wielding mysterious sorcery, he dragged the other men of the Watch with him.
The Night's King and his Corpse Queen ruled the Nightfort for thirteen years without issue. With no unbiased eyes to report his crimes, no one south of the Wall could respond. In time, however, word spread to the leaders of nearby societies. Tales of his atrocities and human sacrifices infuriated every nearby force, inspiring a rare burst of teamwork between contentious figures. Brandon the Breaker, then the King in the North, and Joramun, the King-Beyond-the-Wall, banded together to stop the Night's King. With the head of House Stark and the leader of the wildlings on the same team, the Night's King couldn't resist. Brandon Stark had the Night's King erased from history, every detail of his life, including his name, forgotten to all. Many still share the story, though Maesters argue it was a fairy tale. Bran Stark remembers his Old Nan sharing the parable like this:
He had been the thirteenth man to lead the Night's Watch, she said; a warrior who knew no fear. 'And that was the fault in him,' she would add, 'for all men must know fear.
The Night's King is a legendary horror story that may be fictional within the context of Game of Thrones. George R. R. Martin never shared whether the show's Night King had anything to do with the Night's King. As a historical figure, he's better suited to scaring children and keeping men of the Night's Watch in line than any larger plot necessity. This unique love story changes the way fans look at the White Walkers and the men tasked with keeping them at bay.
