The Shaping of Middle-Earth is the fourth volume of Christopher Tolkien's 12-volume series The History of Middle-earth in which he analyses the unpublished manuscripts of his father J. R. R. Tolkien.

In it the gradual transition from the "primitive" legendaria of The Book of Lost Tales to what would become The Silmarillion is described, and it contains a text which could be seen as the first "Silmarillion": the "Sketch of the Mythology".

Three very interesting other parts are the Ambarkanta or "Shape of the World", a collection of maps and diagrams of the world described by Tolkien; and the Annals of Valinor and Beleriand, chronological works which started out as timelines but gradually turned into full narrative.

Book contents:

1. Prose fragments following the Lost Tales — brief, uncompleted texts which continue on from The Book of Lost Tales
2. The earliest "Silmarillion" — also referred to as the "Sketch of the Mythology", this is the start of the Silmarillion proper
3. The Quenta — a further developed version of the "Sketch", the first full narrative since the Tales
4. The first "Silmarillion" map — a reproduction of the first map of Beleriand
5. The Ambarkanta — cosmological essays, maps, and diagrams
6. The earliest Annals of Valinor
7. The earliest Annals of Beleriand