Arda's creation begins with the Ainulindalë, the Music of the Ainur, orchestrated by Eru Ilúvatar (which is like God) in which the Ainur (which are like SubGods) each contributed themes that shaped the world's destiny. This music brought forth the universe, Eä, including Arda, the world where the stories take place. The Valar and Maiar, wich are powerful Ainur, entered Arda to prepare and govern it, with each having specific roles like Aulë the smith and Ulmo lord of waters.
Initially, Arda was a flat world illuminated by Two Lamps crafted by the Valar to bring light. However, Melkor's jealous destruction of the lamps plunged the world into darkness, leading to reshaping by the Valar. The world was made round later to protect Aman and Middle-earth from evil.
Arda's geography includes continents like Aman in the west and Middle-earth in the east, separated initially by a great sea. The Valar reside in Aman, a realm of bliss and immortality, inaccessible to mortals after the First Age.
If you are intrested in more of middle earth History, check out the History page.
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