The First Age saw the ascend of the Elves, Dwarves and Men and their wars against Morgoth. It ended with the War of Wrath and the drowning of Beleriand. Morgoth was captured by the Valar, ending centuries of dominion in Beleriand.
In the Second Age the Edain prospered in Númenor, but Sauron, a servant of Morgoth also came to dominate the Westlands. The Rings of Power were created as one of such attempts. Sauron's influence also caused the Drowning of Númenor and the Changing of the World. The Age ended with the War of the Last Alliance and the defeat of Sauron.
The Third Age saw the gradual fading of the Elves and also the rise of Sauron against the Númenorian kingdoms, until he was defeated during the War of the Ring. The Age ended some years later with the departure of the White Ship from Mithlond.
Tolkien said in a letter written in 1958 that he believed the Ages had quickened and that it was about the end of the Sixth Age/beginning of the Seventh. However he did not explain the criteria of why the Ages should be shortened.
- ↑ 2.0 2.1 2.2 2.3 J.R.R. Tolkien, The Lord of the Rings, Appendix B
- ↑ 3.0 3.1 J.R.R. Tolkien, Christopher Tolkien (ed.), The Silmarillion, "Of the Rings of Power and the Third Age"
- ↑ J.R.R. Tolkien; Humphrey Carpenter, Christopher Tolkien (eds.), The Letters of J.R.R. Tolkien, Letter 211, (dated 14 October 1958)