Turkic and Sogdian Language contact and the Old Turkic texts with Sogdian Script

Languages are continuously in contact with each other, and these interactions result in changes in these languages at various levels. The results of language contacts not only involve word borrowing but also may lead to the addition of new sounds to a language's phonetic inventory, the formation of new morphemes, and convergence at the syntactic level. Additionally, languages influence each other in terms of writing systems and orthography. It can be traced with historical and linguistic data that the Turkic and Sogdian peoples had lived together in various regions in history since at least the 6th century. First and foremost, the earliest written texts of Turks in the 6th century are in Sogdian. Moreover, the Uyghur writing system was adapted from the Sogdian script, demonstrating that Sogdian orthography served as a model. In the 10th century, particularly in Dunhuang, it is clearly understood that there existed either a bilingual or multilingual Turkish-Sogdian community. The long-term coexistence and changing socio-political circumstances resulted in the relationship between Turkic and Sogdian language becoming highly intricate. The outcomes of this contact were not unilateral. The extensive influence of one language on the other can be observed in both Sogdian and Old Turkic. In this thesis, an attempt is made to identify the effects of the Turkic-Sogdian language contacts on both sides. The influence of Sogdian on Old Turkic, known from the earliest written texts, is attempted to be specifically limited to Sogdian-scripted texts. These texts have a writing style, orthography and dialectal characteristics that are different from Old Uyghur texts. The distinctive linguistic features in Turkic texts written with the Sogdian script are analyzed in terms of orthography, phonology, morphology, and vocabulary. Among these features, efforts are made to identify particularities resulting from the influence of Sogdian and those arising from different dialects.