Religions and religious beliefs such as Islam, Christianity, Judaism, Buddhism, Taoism and Manichaeism lived in the Mongol Empire. Genghis Khan and his descendants tried to treat the spiritual life of the people with maximum tolerance. However, among the rulers some khans gave certain privileges to some religions or were against. At first, the descendants of Genghis supported divinity, but later they showed their inclination towards local religions.

The issue of religion is one of the most important topics in the history of Chaghatai Ulus. The development and economic stability of the state was not decided only by war. Islam had its own role in changing the way of life of Chagatai people, improving international relations and establishing trade relations.

The era of life of Chagatai Ulus coincided with the period when Sufi tarikhats in Central Asia were actively engaged in irshad. The territory of Ulus included large cities such as Bukhara, Samarkand, Kashkar, which were prominent centers of Islamic culture and civilization, and the majority of the local population and army consisted of Muslims. In this way, natural conditions allowed the nomadic Mongol military aristocracy and Mongol tribes to remain under the influence of Islam.

The end of the 13th century - at the beginning of the 14th century, vertical changes were made in the social and economic structure of the Chaghatai Ulus; the clergy replaced the local sedentary aristocracy. However, among the Chaghatai people, Islam spread long and slowly from west to east.

Islam spread among the Chagahtai khans through Mubarak Khan. In the subsequent period, Barak Khan supported the spread of Islam as much as possible, and after Tarmashirin Khan, Islam was finally established and declared as the official religion of the state.