The two merging Russian rivers Volga and Kama, possibly meaning respectively "white" and "black," thus, "west" and "north" as per the oriental tradition. As such, their etymology should be oriental, and Korean might be above all other candidates.
The Turkic peoples associated the Itil's origin with the Kama. Thus, a left tributary to the Kama was named the Aq Itil "White Itil" which unites with the Kara Itil "Black Itil" at the modern city of Ufa.
Volga Bulgaria (...) or Volga–Kama Bulghar, was a historic Bulgar state that existed between the 7th and 13th centuries around the confluence of the Volga and Kama River, in what is now European Russia. Volga Bulgaria was a multi-ethnic state with large numbers of Turkic Bulgars, a variety of Finnic and Ugric peoples, and many East Slavs. The very strategic position of Volga Bulgaria allowed it to create a monopoly between the trade of Arabs, Norse and Avars.
w: Udmurt, perhaps literally meaning "upper river liver" as per Korean. Suggest otherwise!