Like much of Westeros’s history, the Children of the Forest are shrouded in mystery. As the original inhabitants of the continent of Westeros, the Children of the Forest are a species of humanoid creatures that look like young children. They have wide set eyes and their looks are mostly nature driven with green skin, leaves, and twig or branch-like elements on their body. Unlike humans, their lifespan runs across millennia, making them the true inheritors of Westeros, if they do survive. Currently, there is no clarity on whether this race is extinct. We do know that many of them survived Beyond the Wall, and Leaf and her group could possibly be only some of them.
Like Northern families, Children of the Forest worship the old gods of Nature. Their magic coincides with weirwoods and they are said to be the people who carved the faces on heart trees. Green seers and the green sight is also connected to the Children of the Forest.
12,000 years before the events of the book, the First Men crossed the Arm of Dorne from Esos and came to Westeros. In order to make the land more inhabitable, they began to cut down trees, and even cut weirwood trees in the process. As a result, there was a huge conflict between the Children of the Forest and the First Men, which led to subsequent wars. With the First Men being of greater number than the Children of the Forest, the latter were at the losing side of the battle. In order to gain an edge, Leaf, one of the Children of the Forest who lives with the Three Eyed Raven, captured a human man and pushed Dragon glass into his heart, turning him into the Night King.
As the white walkers were out of their control, the Children of the Forest and the First Men joined forces to drive them back, and then built the wall together for their protection. In recent times, no one has seen these mysterious beings and the people who know about them believe them to be a myth.
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