The children of the forest, sometimes referred to simply as the "children" are a mysterious non-human race that originally inhabited the continent of Westeros long before the arrival of the First Men during the Dawn Age more than 12,000 years ago. The giants call them woh dak nag gram ('little squirrel people'). They call themselves those who sing the song of earth in the True Tongue
It is unknown where the children of the forest came from, nor for how long they alone in their land before humans arrived.
For thousands of years the children had to themselves, or shared only with the giants, the landmass that later became known as Westeros. Eventually about 12,000 years ago, the children came in contact with the First Men, the first outsiders. These invaders from Essos brought with them bronze, great leathern shields, the first horses, and their own gods. They burned the great weirwoods as they came, leading to war between the two.
For roughly 2,000 years the two races fought a desperate war for dominance. The children used their magic to shatter the Arm of Dorne, the land-bridge through which the First Men came, in a futile attempt to end the invasion and later flooded the Neck - where legend has it that the children called upon their gods from the Children's Tower to send the hammer of the waters to smash the Neck, as they smashed the Arm of Dorne, but it was not enough to stop the advance of the First Men. The histories say that some of the First Men, the crannogmen, grew close to the children of the forest in the days when the greenseers tried to bring the hammer of the waters down upon the Neck.
Eventually the First Men and the children fought one another to a standstill. The two races agreed to peaceful coexistence and signed the Pact on the Isle of Faces, granting the open lands to humanity and the forests to the children.
The Pact lasted for 4,000 years before the enigmatic Others invaded from the uttermost north, bringing death and destruction to both races, during an extended period of winter known as the Long Night. The children of the forest joined with the First Men, lead by the last hero, to fight against the Others in the Battle for the Dawn. Eventually the Others were driven back into the Lands of Always Winter.
After the Long Night, the First Men and the children of the forest lived in relative peace. In these years, the children of the forest began their slow withdrawal from the lands of men, retreating deeper into their forests and beyond the Wall. During the Age of Heroes it was also recorded by the Night's Watch that the children of the forest gave the black brothers a hundred obsidian daggers every year.
The children of the forest taught the worship of the old gods to the First Men, but the old gods were largely supplanted in the south by the Faith of the Seven after the Andal invasion. A hill, now known to the Westerosi as High Heart, was sacred to the children of the forest. There the Andal king Erreg the Kinslayer cut down the children’s grove of thirty-one weirwoods. High Heart is said to be haunted by the ghosts of the children who died there, likely defending their grove from Erreg. Some of the children’s magic is said to still linger at High Heart.
Relations between the children and humans grew distant over the years, until they ceased altogether. By the time of Aegon's Landing, humans had not seen the children for thousands of years.