Warning: This post contains spoilers for Game of Thrones Season 7 episode 4, "The Spoils of War."
Jon Snow and Daenerys Targaryen finally spent some one-on-one time together—in a dimly lit cave, no less—during Sunday night's Game of Thrones. In a scene in which they explored the dragonglass cave together at Dragonstone, the pair discovered some ancient carvings which, according to Jon, were left behind by the Children of the Forest.
Their connection to the current events on the show is important, so here's a refresher on who these mysterious, humanoid Children really are.
Barely taller than human children, the Children of the Forest get their name from their childlike facial features and large, rounded eyes. In the A Song of Ice and Fire books, the Children are often referred to as "dark and beautiful" with "nut-brown skin, large ears, and glowing gold eyes, slitted like a cat's." They're also said to have skin with spotted patterns and four-digit hands that end in small claws. On the HBO series, the Children are depicted as having normal, human-like hands.
The Children like to dwell in the depths of hidden forests, deep swamps, and dark caves like the one Jon and Dany explored. Since ancient times, they've embraced their connection with nature and animals, even fashioning bows out of Weirwood and using dragonglass blades to hunt. Some of the wiser Children were known as Greenseers and are said to have possessed impressive magical abilities. Worshipping the Old Gods of the Forest, the Children even carved faces into the sacred Weirwood trees in honor of the nature gods.
A non-human race, the Children of the Forest were the original inhabitants of Westeros, long before the First Men migrated to the continent over 12,000 years ago. When the First Men arrived and began cutting down the forests, the Children defended themselves in several brutal wars over the course of 2,000 years.
At the end of the second millennium, the two groups fought until they reached an impasse, after which they signed a pact and agreed to coexist, with the humans taking the open land and the Children residing in the forests. Their people mostly dead and their culture forgotten, the Children of the Forest stayed in hiding for another 2,000 years until the White Walkers—which they created to defend themselves from the First Men—invaded, forcing the Children to ally with the First Men and defend themselves for the next 8,000 years.
It's possible this was when the children carved their markings warning others of the White Walkers. These strange swirls and symbols are said to represent the ability of the children to work together alongside man to defeat their common enemy, the White Walkers—an idea Jon recently used in his favor to win Dany over.
The Children suffered yet again when the Andals conquered Westeros, killing many of the remaining members of their species and cutting down almost all their sacred heart trees. Any of the Children who survived fled to the far north, where they hid in vast underground caverns and were not seen again for thousands of years. According to legend, after the defeat of the White Walkers, the Children used their powerful magic to keep the ice creatures away for good by helping Bran the Builder raise the Wall.
Despite these efforts, the Children might have known the Wall wouldn't keep the White Walkers away for good. While it's uncertain what the cave drawings Jon and Daenerys found really signify, it's possible the Children left these swirl patterns behind to warn others that the fight between the living and the dead may eventually come full circle.
Unlike many Game of Thrones characters who first popped up in Season 6 of the show, the Children were first mentioned way back in Season 2, when told that the Children of the Forest had long been thought extinct and forgotten, and many people doubted they ever even existed at all. In Season 4, we finally get to meet one of the Children, Leaf, who emerges from the Three-Eyed Raven's cave to save Bran and his travel companions from being attacked by a group of wights.
Then, apart from a brief mention in Season 5, when Sam discovered the Children used to hunt with dragonglass weapons, the mysterious creatures aren't mentioned again until Season 6, when they're seen with Bran at the Three-Eyed Raven's cave. Bran has a vision revealing the Children created the White Walkers, and Leaf even took part in the process (this suggests her kind can live for thousands of years). Leaf explains to Bran that her people had no other choice to defend themselves from the First Men. Later, she and the remaining Children help defend Bran in his battle against the Night King, though most of them do not survive. Leaf makes the ultimate sacrifice when she shields Bran and the others from an explosive weapon, giving up her own life and possibly marking the end of her species.
So what role might the Children of the Forest play in future Game of Thrones episodes? Considering they might be extinct after Leaf's sacrifice, it's difficult to say. At the very least, the carvings Jon and Daenerys discovered in the latest episode might finally push Dany to believe she has much more to worry about than who's going to sit on the Iron Throne.