J.R.R. Tolkien chiefly used Finnish as the model for Quenya.
Quenya is one of Tolkien’s Elvish languages, and its sound and grammar were strongly influenced by Finnish. Tolkien encountered Finnish through the national epic Kalevala, whose language and mythology fascinated him. Quenya was not simply Finnish with changed vocabulary; Tolkien constructed it as an original language with its own history, forms, and fictional speakers.
Tolkien also drew on other languages when developing his linguistic families. Welsh influenced the sound patterns of Sindarin, while Old English, Old Norse, and Germanic languages contributed to other parts of his worldbuilding. The relationships between the languages of Middle-earth reflect Tolkien’s professional interest in historical linguistics.