What was the first movie or show to use a conlang?
Def: Conlangs: an invented language intended for human communication that has planned and cohesive phonological, grammatical, and syntactical systems. They can be a priori languages
I've listed a (very well known) few of them:
- Elvish - The Lords of the Rings
- High Valyrian and Dothraki - Game of Thrones
- Klingon - Star Trek
- Na'vi - Avatar
- Barsoomian - John Carter
I'm not taking into account made-up languages like parseltongue (Harry Potter) or Mangani (Tarzan) because they're intended to talk to/with animals and not interact with humans (or alike).
I'm not taking into account either some languages like Nadsat (A Clockwork Orange) or Newspeak (1984) because they derived from existing languages and/or slang words, and were not invented (from imagination) and constructed languages. These probably rank amongst the anti-languages like thieves' Cant, Polari, and Gobbledygook and many others.
To be as accurate as possible, Huttese (StarWars) (derived from Quechua, a native American language of the Andes region, and other Peruvian languages and it does have similarities with long-dead languages such as Mayan and Nahuatl (spoken by the Aztecs in Mexico)) or Wakandan (Wakanda Forever) (derived from Xhosa and Nguni languages) or similar languages should normally not qualify as conlangs too but I may be wrong, so please comment/correct if necessary.
As the moment, I've found no older than the 1974 TV series Land of the Lost.
NOTE: conlangs have a long history, as earlier as 12th century Lingua Ignota, as well as in books. I'd like to focus on conlangs for M&TV but any reference to books is welcome. ie. New Language (1909) has been used in "that wonderful movie you know and that no one never heard of" (1946).
NOTE: from comment, to clarify the expected outcome for this question. I try to spot a fantasy language that was used in movie or tv show. It has to be an invented language, fully functional like the definition of the dictionary. It can be first invented for a book, then used in the movie, or directly created for the movie. As examples, Elvish would qualify (1st in a book in 1954, then in a movie in 1978 then 2001) but Esperanto (1887) would not qualify, as it's intended to be a universal second language for international communication.