As late as the early tenth/16th century there were still in...

As late as the early tenth/16th century there were still in the Imperial Chancellery in the Istanbul scribes skilled in writing the Uygur script. The Uygur Turkish or, to use a more suitable term, the old Turkish literary language (for the civilization that used it was wider than the geographical or historical limits of the Uygur State) shows, broadly speaking, the same dialectical peculiarities as the Kot Turkish monuments.

The few dialectical divergences are obviously in the main due to the passage of time and to influence from the outside.[^1] The conversion to Islam of the Turks of Central Asia began in the fourth/tenth century. Throughout history the Turks proved to be devoted Muslims and zealous defenders and promoters of Islam.

Founded on the literary Uygur of the pre-Islamic period, there developed in the fifth/11th century under the Karakhanids, converts to Islam, the Muslim Turkish literary language of East Turkestan written probably from the first in the Arabic alphabet. The best known documents in this language are two didactic poems, the Qutadhghu Bilig (The Science of Happiness), composed by Yusuf Khas Hajib, and the ‘Atabat al-Haqa’iq (The Threshold of Facts), composed by Adib Ahmad.

There is, further, a translation of the Qur’an. Besides these works there is another dating from the same century, the Diwan-o Lughat al-Turk of Mahmud al-Kashghari composed in Baghdad in Arabic in order to acquaint the Arabs with the Turkish world. It is a very valuable source for the investigation of the various Turkish tribes, dialects, folk literature, customs, culture, etc. of this time.[^2] Islam was established in the fourth/tenth century in the Bulghar kingdom of Kama also.

But data are lacking to enable us to decide if there also existed any literature. In any case Bughar elements are found in the sepulchral inscriptions of the eighth/14th century in the Volga region.[^3] The development of literary Turkish in central Asia went on without interruption, but its centres changed from time to time.

The absence of early manuscripts prevents us from giving a definite name to the language of the Hikmats (theological didactic poems) of Ahmad Yasavi, the founder of Turkish mysticism, who lived in the sixth/12th century in West Turkestan. In the seventh/13th century the various literary dialects of the Muslim Turkish world were not yet clearly differentiated from one another.