{2018}And evidence points to the Indo-Iranian superstrate of the Mitanni being Indo-Aryan rather than Iranian, fascinatingly. (The Hurrian mainstay of the Mitanni had already been in the region for quite some time, of course. Some linguists suggest that the Kassites who plagued the Sumerians may have been cousins of the Hurro-Urartians, but attestations of Kassite are so limited that I imagine that would be hard to prove.)
I imagine most material would be in the form of names, rendered in Aramaic and-or Sumerian -- the script of the scribes. It'd be a good starting point, at least, yes?
thank you