::Hi Again. You said: "Kurdish is grammatically closer to altaic-languages like Turkish.".  That is not true at all and it is classified under Iranian language and some versions of it are very close to Persian (Kalhori, Feyli).  Also Arranian language was not Khazarian and Muqaddesi actually calls the language of Azerbaijan (part of the 8th region) as Persian.  Soo does Masudi.  So does Ibn Hawqal.  There is not a single reference that Khazar was spoken in Aran.  Baluchs are not Turkich tribe and Masudi got it wrong in this case.  Their nomadic lifestyle might have lead to confuse it , or it was a manuscriptal era, or perhaps you are quoting it wrong.   There was some Khazar officers(originally slaves) in Baghdad (like Boga) but they were sent from Baghdad and originally they were not from below the caucus.  These were originally Jewish but were converted when they were sent and raised in Baghdad.  Anyhow, there are too many issues that can be discussed, but the important issue is to bring valid English sources (not translations)(with proper citation) or actual original (Arabic, Persian) (not through an intermediatory source).  Thanks!