The monograph highlights the ideological evolution of Ottoman society in the 19th century, the origin and development of the official doctrines of Ottomanism and pan-Islamism, analyzes the forms of their embodiment in state practice, as well as the role that these doctrines were called upon to play in strengthening the unity of the Ottoman Empire. The religious situation in the empire and the stages of the formation of the pan-Islamist movement in the last third of the 19th century are considered.