erzjan' kel'
The Russian Orthodox Church has its 16th patriarch, Kiril I (né Vladimir Mikhailovich Gundyayev; Wikipedia; Novinite). According to the Wikipedia article he is of Erzya-Mordvin ethnic origin. Erzya (Эрзянь кель) is a Finno-Ugric language with about half a million speakers. Reading up on Erzya led me to the Finno-Ugric Electronic Library (link). (The English interface has some problems, but for those who read Russian it’s a good resource.)