[SunkenCiv]

May have been them but could have been one of the imperial powers from just over the threshold of the age of literacy — the Elamites (who had a writing system, but it can’t be read, so far) would be a guess. The Indo-Europeans entered Europe and the Middle East (and India, for that matter) in a series of waves, which at least in part coincide with the global climate cycles.

[Verginius Rufus]

Apparently there are two early Elamite writing systems that are still undeciphered, but there are cuneiform texts in Elamite which can be read. One of the three languages on the Behistun or Bisutun inscription of Darius I is Elamite. It doesn't seem to be related to any other known language (possibly distantly related to Dravidian). They were down there along the Persian Gulf--I don't know if they would bother to go all the way to Turkey.

There is an Elamite king mentioned in Genesis 14, and a mention of Elamites in Acts 2.9 (present in Jerusalem).