Middle-earth is the name used for J. R. R. Tolkien's fictional ancient Earth where the stories in his legendarium take place. "Middle-earth" is a literal translation of the Old English term Middangeard, referring to this world, the habitable lands of men. Mythologically, the Endor continent became the Eurasian land-mass after the primitive Earth was transformed into the round world of today. Although Middle-earth's setting is often thought to be another world, Tolkien actually conceived it as a fictional period in our Earth's own past 6,000 to 7,000 years ago.
The history of Middle-earth is divided into several Ages: The Hobbit and The Lord of the Rings deal exclusively with events towards the end of the Third Age and at the dawn of the Fourth Age, while The Silmarillion deals mainly with the First Age. The world (Arda) was originally flat but was made round near the end of the Second Age by Eru Ilúvatar, the Creator.
In the works of J. R. R. Tolkien, Arda is the world in which all of the events occur, including the continents of Middle-earth and Aman. Arda was part of Eä, the universe of all which exists. Arda was created, together with the rest of Eä, through the Music of the Ainur for the Children of Ilúvatar (that is, Elves and Men).
Because the Sun, Moon, stars, and other objects orbited the planet in the cosmology of Middle-earth they were considered part of Arda, leading to Arda sometimes being called the 'Solar System' of Middle-earth. The term for the Earth itself, excluding these celestial bodies, was Ambar or Imbar.
See Middle-earth for the main article about Tolkien's fictional universe
Originally a flat world, the continents were surrounded by a mighty ocean (or perhaps by space), Ekkaia or the Encircling Sea, and separated by Belegaer, called the Great Sea. In the First Age, the area north and west of Middle-earth was occupied by the country of Beleriand, but this was destroyed during the War of Wrath.
In the Second Age, Númenor was raised in the Great Sea for the Edain. This island existed through most of the Second Age, but was destroyed as a result of the pride of the Númenórean people in defying the Ban of the Valar and sailing to Aman in the west.
After the destruction of Númenor, Arda was made round. Aman (The Undying Lands) was taken out of the world into an alien dimension, and could only be reached by the Elves, following the straight road that was granted to them. As Aman was taken away from Arda, new lands and continents were created.
South of Middle-earth was the Dark Land and east of it was the Land of the Sun.
Here are some open tasks for WikiProject Middle-earth. Feel free to help with any of the following tasks:
Collaboration: Return Middle-earth to featured status, make Lord of the Rings a good article.
Cleanup: List of Hobbits, List of hobbit families, Second Age
Copyedit/extensive work: Círdan, Meriadoc Brandybuck, Valaquenta
Create: J. R. R. Tolkien: A Descriptive Bibliography, Kay Miner, Tolkien's View: Windows into his world
Expand to separate pages/list entries: Alliterative verse by J. R. R. Tolkien, Art inspired by J. R. R. Tolkien, Nellas
Stubs: The Lord of the Rings: A Reader's Companion, Tolkien Studies, Images of Middle-Earth
Provide references: The Notion Club Papers
Add secondary sources: Númenor, Moria (Middle-earth)
Current topics (may need updating): The History of The Hobbit, The Hobbit films
Merge into: Minor places in Middle-earth, Minor places in Beleriand
Other: See the Things to do page, update a Random article , or review recent changes