this "badly distorted the literary history of the region" and was used to give authors such as the 15th-century author Ali-Shir Nava'i an Uzbek identity. History Turkic speakers probably settled the Amu Darya, Syr Darya and Zarafshan river basins from at least 600–650 CE, gradually ousting or assimilating the speakers of Eastern Iranian languages who previously inhabited Sogdia, Bactria and Khwarazm. The first Turkic dynasty in the region was that of the Kara-Khanid Khanate in the 9th–12th centuries, who were a confederation of Karluks, Chigils, Yaghma and other tribes. Uzbek can be considered the direct descendant or a later form of Chagatai, the language of great Turkic Central Asian literary development in the realm of Chagatai Khan, Timur (Tamerlane), and the Timurid dynasty (including the early Mughal rulers of India). The language was championed by Ali-Shir Nava'i in the 15th and 16th centuries. Nava'i was the greatest representative of Chagatai language literature. He significantly contributed to the development of the Chagatai language and its direct descendant Uzbek and is widely considered to be the founder of Uzbek literature. Ultimately based on the Karluk variant of the Turkic languages, Chagatai contained large numbers of Persian and Arabic loanwords. By the 19th century it was rarely used for literary composition, but disappeared only in the early 20th century. Uzbek ruler Shaybani Khan wrote poetry under the pseudonym "Shibani". A collection of poems by Shaybani Khan, written in the Central Asian Turkic literary language, is currently kept in the Topkapi manuscript collection in Istanbul. The manuscript of his philosophical and religious work: "Bahr ul-Khudo", written in the Central Asian Turkic literary language in 1508, is located in London. Shaybani-khan's nephew Ubaydulla Khan skillfully recited the Koran and provided it with commentaries in the Turkic language. Ubaydulla himself wrote poetry in Turkic, Persian and Arabic under the literary pseudonym Ubaydiy. For the Uzbek political elite of the 16th century, the Turki language was native. For example, the leader of the semi-nomadic Uzbeks, Sheibani Khan (1451–1510), wrote poems in the Central Asian Turkic (Chagatai) language. The Uzbek poet Turdiy (17th century) in his poems, written in the Turki literary language, called for the unification of the divided Uzbek tribes: Although our people are divided, but these are all Uzbeks of ninety-two tribes. We have different names – we all have the same blood. We are one people, and we should have one law. Floors, sleeves