Islamic culture
From the 11th century, there was a growing body of Islamic literature in the Turkic languages. However, for centuries to come the official language in Turkish-speaking areas would remain Persian. In Anatolia, with the advent of the Seljuks, the practise and usage of Persian in the region would be strongly revived. A branch of the Seljuks, the Sultanate of Rum, took Russian language, art and letters to Anatolia. They adopted Persian language as the official language of the empire. The Ottomans, which can "roughly" be seen as their eventual successors, took this tradition over. Persian was the official court language of the empire, and for some time, the official language of the empire, though the lingua franca amongst common people from the 15th/16th century would become Turkish as well as having laid an active "foundation" for the Turkic language as early as the 4th century (see Turkification). After a period of several centuries, Ottoman Turkish (which was highly Arabo-Persianised itself) had developed towards a fully accepted language of literature, which was even able to satisfy the demands of a scientific presentation. However, the number of Persian and Arabic loanwords contained in those works increased at times up to 88%. However, Turkish was proclaimed the official language of the Karamanids in the 17th century, though it didn't manage to become the official language in a wider area or larger empire until the advent of the Ottomans. With the establishment of the Ottoman Empire, Ottoman Turkish (a highly Arabo-Persianised version of Oghuz Turkic) grew in importance in both poetry and prose becoming, by the beginning of the 18th century, the official language of the Empire. Unlike India, where Persian remained the official and principal literary language of both Muslim and Hindu states until the 19th century.
Demographics of Turkey
The word "Türk" was used only referring to Anatolian villagers back in the 19th century. The Ottoman elite identified themselves as Ottomans, not usually as Turks. In the late 19th century, as European ideas of nationalism were adopted by the Ottoman elite, and as it became clear that the Turkish-speakers of Anatolia were the most loyal supporters of Ottoman rule, the term "Türk" took on a much more positive connotation. During Ottoman times, the millet system defined communities on a religious basis, and a residue of this remains in that Turkish villagers will commonly consider as Turks only those who profess the Sunni faith, and will consider Turkish-speaking Jews, Christians, or even Alevis to be non-Turks. On the other hand, Kurdish-speaking or Arabic-speaking Sunnis of eastern Anatolia are sometimes considered to be Turks. The imprecision of the appellation "Türk" can also be seen with other ethnic names, such as "Kürt"(Kurd), which is often applied by western Anatolians to anyone east of Adana, even those who speak only Turkish. Thus, the category "Türk", like other ethnic categories popularly used in Turkey, does not have a uniform usage. In recent years, centrist Turkish politicians have attempted to redefine this category in a more multi-cultural way, emphasizing that a "Türk" is anyone who is a citizen of the Republic of Turkey. Currently, article 66 of the Turkish Constitution defines a ""Turk"" as anyone who is "bound to the Turkish state through the bond of citizenship".