Old Turkic (also East Old Turkic, Orkhon Turkic language, Old Uyghur) is the earliest attested form of the Turkic languages, found in Göktürk and Uyghur Khaganate inscriptions dating from about the seventh to the 13th century. It is the oldest attested member of the Siberian Turkic branch of Turkic, which is extant in the modern Western Yugur language.

Bulgar (also known as Bulghar, Bolgar, or Bolghar) is an extinct Oghur Turkic language spoken by the Bulgars.. The name is derived from the Bulgars, a tribal association that established the Bulgar state known as Old Great Bulgaria in the mid-7th century, giving rise to the Danubian Bulgaria by the 680s. While the language was extinct in Danubian Bulgaria (in favour of Old Church …