The Sleep of Yavanna refers to a period in Middle-earth's history between the Spring of Arda and the rising of Moon and Sun, during which almost all living things slept and Middle-earth was lit only by starlight.
History
After the destruction of the Two Lamps by Melkor before the Two Trees, Yavanna needed to see that they were protected so she sent them to sleep until light returned again to Middle-earth. At this time the only life in Middle-earth were the Elves, Dwarves, and the monstrous servants of Melkor before and after his first defeat.
The period ended with the rise of the Moon and Sun which began the First Age of Middle-earth.[1]
References
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