Warning: SPOILERS ahead for Game of Thrones season 8, episode 1, "Winterfell"
The Night King left a grim message in the Game of Thrones season 8 premiere, featuring a spiral design that we've seen in the show before. In one of the final scenes of "Winterfell," Tormund and Beric rendez-vous with Jon's old friend "Dolorous" Edd Tollett at Last Hearth, the ancestral home of House Umber. Unfortunately, the only Umber they found was young Ned Umber, who was impaled on a wall in the center of a grisly spiral of made of severed limbs.
To make matters worse, Ned Umber was not dead but undead: turned into a wight by the Night King. Beric put him out of his misery with his flaming sword, setting fire to the spiral as well. It's been a while since the last season of Game of Thrones, so you could be forgiven for not remembering it, but this spiral has actually been in the show several times. In season 3, Jon came across some horses belonging to the Night's Watch, cut up and arranged in a similar spiral. Jon also saw the same spiral pattern carved on the walls of caves in Dragonstone.
The spiral pattern was originally attributed to the Children of the Forest, the ancient race who guided Bran in Game of Thrones season 6. In the episode "The Door," Bran sees a vision of the Children of the Forest stabbing a man (notably played by the same actor who plays the Night King, Vladimir Furdik) with a dragonglass dagger and seemingly creating the first White Walker. The White Walkers themselves then adopted the spiral as one of their symbols, using it as a way to display the bodies of their victims - including poor Ned Umber.
Here are the instances of the spiral we've seen before - starting with the slaughtered horses north of the Wall:
Here's a spiral of stones surrounding the weirwood tree where the Children of the Forest created the Night King:
Here's the spiral among the cave drawings on Dragonstone. The White Walkers have also arranged bodies in the shape of another symbol from these caves:
So, what's the significance of the spirals? We know that they were originally used by the Children of the Forest, and that they were then adopted by the White Walkers. There's animosity between those two factions, so there's a strong likelihood that the Night King and his cohorts use the symbols of the Children of the Forest in their acts of horrific violence as a kind of blasphemy against their creators. However, there are also other theories.
Some fans have speculated that the symbols actually have powerful magical properties, and that ritual sacrifices are used to advance the cold weather south - essentially conjuring the winter. Another theory is that the Night King is an ancient Targaryen (a theory bolstered by the fact that he's able to ride a dragon), and that the spirals are somehow connected to a similar pattern in the Targaryen sigil:
We may learn more about the precise meaning and history of the spiral in the final five episodes of Game of Thrones, or it may simply remain an intriguing aspect of Westerosi history that's never elaborated upon further. One thing is certain: if Jon and Daenerys can't find a way to stop the Night King and his army, there will be more gruesome spiral symbols to come.
Game of Thrones returns to HBO @9pm on Sunday, April 21.