The lore surrounding The Lord of the Rings is so expansive that it can sometimes be difficult to keep up with. The world Tolkien created is so detailed that there are many places that the story never even visits, but they are still important to the world at large. The lore goes deep enough that there is a whole mythology surrounding the creation of the world and the extended history of Middle-earth, and because it is secondary to the story, often only the most die-hard fans even know about it.
One of the more confusing elements is differentiating between the different names for the lands in Tolkien's work, and how the world as a whole is established. Middle-earth, Arda, and Beleriand are all terms that are used when referring to the world Tolkien created, but they all mean different things and may be dependent on what time period is being discussed. So what are the differences between these places, and how are they important to Tolkien's world?
LOTR: Questions About Middle-Earth That Tolkien Never Answered
The term Arda simply refers to the world as a whole, the way that we call the planet we inhabit «Earth». Arda was created using the Music of the Ainur, as a way to create a home for the Children of Ilúvatar (the races of Elves and Men). The Valar came up with the geography of Arda and gave it form, until Melkor decided he wanted Arda for himself and tried to fight them for it. This resulted in the First War, which marred Arda and changed the plan for its layout.
Originally, Arda was flat, and the continents were surrounded by Ekkaia, the Encircling Sea. Aman was the biggest continent, and it lay in the West, and Middle-earth was to the East. Middle-earth was joined to Aman in the Northwest by the Helcaraxë, a cold, icy
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