Excerpt from Turbine's Lorebook's entry on the first age:
- First, and shortest by far, of the Four Ages chronicled by Tolkien. Unlike the Second and Third Ages, there is no detailed chronicle of the events of the First Age, and so dates must be inferred from references in the text - hence many dates in this Age (including the year in which it ended) are necessarily approximate.
- The First Age began with the return of the Noldor to Middle-earth, the first rising of the Moon and the Sun, and the awakening of the first Men. It ended with the destruction of Beleriand and the final defeat of Morgoth. The end of the First Age was marked by the return of many of the Noldor, accompanied also by many Sindarin Elves, into the West to dwell on Tol Eressëa.
The First Age is the setting for the books The Silmarillion and The Children of Húrin and is considered Ancient History with respect to the time period for the Lord of The Rings Online game.
- First Age of the Children of Ilúvatar] From Wikipedia