السغدية

Sogdian was an Eastern Middle Iranian language of the Sogdians, the great Silk Road merchants whose city-states (Samarkand, Bukhara, Panjikent, Tashkent) controlled the Central Asian trade routes from the 4th to 9th centuries CE. Sogdian colonies along the Silk Road as far as Dunhuang and Turfan made it a lingua franca of Eurasian trade. Surviving texts include the Ancient Letters (313 CE) from Dunhuang, Manichaean and Buddhist literature, and Christian fragments. The Sogdian script (Aramaic-derived) is the direct ancestor of the Old Uyghur script and indirectly of Mongolian and Manchu scripts. Modern Yaghnobi (yai) is its sole surviving descendant in the Tajik Yaghnob valley.