The philologist and fantasy author J. R. R. Tolkien created the first of these languages, including Quenya and Sindarin.
[1] The languages were the first thing Tolkien created for his mythos, starting with what he originally called "Qenya", the first primitive form of Elvish.
[2] Tolkien conceived a family tree of Elvish languages, all descending from a common ancestor called Primitive Quendian.
[3] In addition to Quenya and Sindarin, he sketched several other Elvish languages in far less detail, such as Telerin, Nandorin, and Avarin.
In addition to Tolkien's original lexicon, many fans have contributed words and phrases, attempting to create a language that can be fully used in reality.