Maia (Middle-earth) in the context of "Halls of Mandos"

The Valar (['valar]; singular Vala) are characters in J. R. R. Tolkien's Middle-earth writings. They are "angelic powers" or "gods" subordinate to the one God (Eru Ilúvatar). The Ainulindalë describes how some of the Ainur choose to enter the world (Arda) to complete its material development after its form is determined by the Music of the Ainur. The mightiest of these are called the Valar, or "the Powers of the World", and the others are known as the Maiar.

Valinor (Quenya: Land of the Valar), the Blessed Realm, or the Undying Lands is a fictional location in J. R. R. Tolkien's legendarium, the home of the immortal Valar and Maiar on the continent of Aman, far to the west of Middle-earth; he used the name Aman mainly to mean Valinor. It includes Eldamar, the land of the Elves, who as immortals are permitted to live in Valinor.

The name "the Undying Lands" does not mean that the land itself causes mortals to live forever. Generally, only immortal beings are allowed to reside there. Exceptions are made for the surviving bearers of the One Ring: Bilbo and Frodo Baggins and Sam Gamgee, who dwell there for a time, and the dwarf Gimli.

The Silmarillion (Quenya: [silmaˈrilːiɔn]) is a book consisting of a collection of myths and stories in varying styles by the English writer J. R. R. Tolkien. It was edited, partly written, and published posthumously by his son Christopher in 1977, assisted by Guy Gavriel Kay, who became a fantasy author. It tells of Eä, a fictional universe that includes the Blessed Realm of Valinor, the ill-fated region of Beleriand, the island of Númenor, and the continent of Middle-earth, where Tolkien's most popular works—The Hobbit and The Lord of the Rings—are set. After the success of The Hobbit, Tolkien's publisher, Stanley Unwin, requested a sequel, and Tolkien offered a draft of the writings that would later become The Silmarillion. Unwin rejected this proposal, calling the draft obscure and "too Celtic", so Tolkien began working on a new story that eventually became The Lord of the Rings.

The Silmarillion has five parts. The first, Ainulindalë, tells in mythic style of the creation of Eä, the "world that is." The second part, Valaquenta, gives a description of the Valar and Maiar, supernatural powers of Eä. The next section, Quenta Silmarillion, which forms the bulk of the collection, chronicles the history of the events before and during the First Age, including the wars over three jewels, the Silmarils, that gave the book its title. The fourth part, Akallabêth, relates the history of the Downfall of Númenor and its people, which takes place in the Second Age. The final part, Of the Rings of Power and the Third Age, tells the history of the rings during the Second and Third Ages, ending with a summary of the events of The Lord of the Rings.

Morgoth Bauglir ([ˈmɔrɡɔθ ˈbau̯ɡlir]; originally Melkor [ˈmɛlkor]) is a character, one of the godlike Valar and the primary antagonist of Tolkien's legendarium, the mythic epic published in parts as The Silmarillion, The Children of Húrin, Beren and Lúthien, and The Fall of Gondolin. The character is also briefly mentioned in The Lord of the Rings.

Melkor is the most powerful of the Valar but he turns to darkness and is renamed Morgoth, the primary antagonist of Arda. All evil in the world of Middle-earth ultimately stems from him. One of the Maiar of Aulë betrays his kind and becomes Morgoth's principal lieutenant and successor, Sauron.

The fictional races and peoples that appear in J. R. R. Tolkien's fantasy world of Middle-earth include the seven listed in Appendix F of The Lord of the Rings: Elves, Men, Dwarves, Hobbits, Ents, Orcs and Trolls, as well as spirits such as the Valar and Maiar. Other beings of Middle-earth are of unclear nature such as Tom Bombadil and his wife Goldberry.