Tolkien's Middle-earth family trees contribute to the impression of depth and realism in the stories set in his fantasy world by showing that each character is rooted in history with a rich network of relationships. J. R. R. Tolkien included multiple family trees in both The Lord of the Rings and The Silmarillion; they are variously for Elves, Dwarves, Hobbits, and Men.
The family trees gave Tolkien, a philologist, a way of exploring and developing the etymologies and relationships of the names of his characters. They imply, too, the fascination of his Hobbit characters with their family history. A further function was to show how aspects of character derive from ancestry.