The Children of Ilúvatar
Elves and Men; the Firstborn and the Followers
Definition
The Children of Ilúvatar — in Quenya Eruhíni — are the two races that Eru alone created directly, without intermediary: the Elves and Men. They are “the Children of Ilúvatar… the Eldar (or Elves) and the Atani (or Men)”. To them alone he gave free will and a soul (“fëa”) directly; the rest of the living world was made or adopted by others. The Valar “knew not the Children… when they were yet uncreated”, and the whole history of Arda — the shaping of Middle-earth, the awakening, the wars of the Valar — is ordered to prepare a dwelling for them.
The Firstborn: Elves
“The Firstborn” Their nature: souls (fëa) and bodies(hröa) bound; “they are not subject to sickness or death by age”, and their long memory and sorrow are the harp of the legendarium. Some were lured away to Valinor (the Eldar); some stayed behind (the Avari); all are “the Elder Kindred”.
The Followers: Men
“The Followers” They are later, more frail, their coming changed the music; “the theme of Men is different” — above all, they die, and their deaths are “the one thing… beyond the design of the Valar”.
The Adopted Children
Beyond the Two Kindreds , Eru adopted other races at their makers’ plea and hallowed them: The Dwarves, wrought by Aulë and given life and free will by Eru;
- The Ents, shepherds of the trees, called forth at Yavanna's prayer;
- The Eagles of Manwë (in the sense of the consecrated creatures served as messengers). None of these are “Children of Ilúvatar” in the strict sense — that name is reserved for Elves and Men — but all are “children of the One” by adoption, and their fates are interwoven with the Children’s.
In the Tale
The Children are the axis of the whole story: for their sake the Valar entered the world, Melkor corrupted his own works to destroy them, the Silmarils were hallowed, and the great dooms spoken. The love between Elves and Men
— the marriages of Beren and Lúthien, Tuor and Idril, Aragorn (treated under their kindreds) — are the highest theme of the legendarium: the union of the immortal and the mortal, from which descend the Half-elven and the kings of the Dunedain.