Introduction. The article examines some rites and customs once practiced in the medieval ethnopolitical alliance of Moghuls. Goals. The study attempts an insight into Tarikh-i Rashidi by Mirza Muhammad Haidar Dughlat for data pertaining to customs and rituals of the medieval Moghuls. Materials and methods. The study focuses on medieval Eastern Muslim historical sources — primarily the well-known Persian-language Tarikh-i Rashidi — as well as related scholarly publications. So, those are messages from Tarikh-i Rashidi by Mirza Muhammad Haidar of the Moghul Dughlat that serve as key reference data. The work employs the descriptive, historical comparative and other generally accepted research methods. Results. Our insights into Tarikh-i Rashidi by Mirza Muhammad Haidar have yielded some discoveries of rites and customs once spread among the Moghul tribes. These are of significant interest, since they cast some light on interior life of the medieval Moghuls that has remained virtually unattended by researchers of the past. Some of the Moghul customs and rituals mentioned in Tarikh-i Rashidi had also been witnessed among other ethnopolitical alliances of the Middle Ages. And some of the customs have even survived to date. For example, the First Kumis Festival used to be celebrated by many Turko-Mongols, including Kazakhs. Furthermore, the Moghul custom of yangilik is comparable enough to the Kazakh custom of amengerlik. Other customs and rituals of Moghuls described in the historical work under consideration need additional investigations with the involvement of new materials from historical sources and ethnographic data on modern Turkic and Mongolic peoples.