Old Turkic

Old Turkic, also known as East Old Turkic, was a Siberian Turkic language spoken around East Turkistan and Mongolia. It was first discovered in inscriptions originating from the Second Turkic Khaganate, and later the Uyghur Khaganate, making it the earliest attested Common Turkic language. In terms of the datability of extant written sources, the period of Old Turkic can be dated from slightly before 720 AD to the Mongol invasions of the 13th century.

From Wikipedia · Old Turkic · CC BY-SA 4.0