Ages of Middle-earth

Ages is the term used to divide and describe certain periods of history in Middle-Earth. Ages do not have exact lengths of time. A new one usually starts after the current Dark Lord is overthrown.

There are four main Ages in Middle-Earth.

The First Age, which was covered by most of The Silmarillion.

The Second Age, which is hardly covered at all, but what we have is in the last bit of The Silmarillion, Unfinished Tales, and the Tale of Years in The Lord of the Rings.

The Third Age, the end of which was covered in The Hobbit and The Lord of the Rings.

The Fourth Age, which no one knows much about because it was only just beginning at the end of Lord of the Rings. It was presumably very peaceful, as there were no more Dark Lords to wreak havoc.