The Kereyit were a tribal confederation of Mongol or Turkic origin that inhabited the Altai-Sayan region in the 12th century. As one of the five major tribes of the Mongolian steppe, the Kereyit played a significant role in terms of both population density and territorial extent. A distinguishing feature of the Kereyit was their collective conversion to the Church of the East (Nestorian Christianity) in the early 11th century. This transformation contributed to the emergence of various legends, including the myth of "Prester John," which circulated in Europe over time. The political and religious influence of the Kereyit increased when their tribal leaders officially embraced Christianity in the 11th century. This acceptance had widespread repercussions not only within the tribe but also among neighboring communities. Europeans had established diplomatic and commercial relations with the Kereyit and were familiar with them up to approximately 300 years before the Mongol invasions. The power of the Kereyit extended as far as the Great Wall of China, making them a formidable presence in the Mongolian geographical sphere. During the rise of Genghis Khan, the Kereyit remained a significant political force under the leadership of Toghrul Khan (also known as Togrul or Ong Khan). Toghrul Khan was initially an ally of Genghis Khan but later became his adversary, leading to conflicts that ultimately resulted in the subjugation of the Kereyit by Genghis Khan. Consequently, the Kereyit, along with other Mongol Christian tribes, were compelled to submit to Genghis Khan’s political ambitions. The Kereyit held a unique position in the Mongol-Turkic world due to their religious and political structures. Their integration of Christian beliefs with the traditional nomadic social order made them an intriguing subject for both the Eastern and Western worlds. This significant element of Mongol and Turkic history not only shaped Asia’s political and cultural landscape but also contributed to the historical development of Europe. The Kereyit played a crucial role in the political, cultural, and religious transformations of the Mongolian region. In this context, examining the influence of Kereyit-origin figures in Mongol history is essential not only for understanding the dynamics of inter-tribal relations but also for shedding light on the Mongols' perspectives on Christianity, diplomacy, and governance. In particular, the political alliances and hostilities of leaders such as Toghrul Khan profoundly influenced the rise of Genghis Khan and the formation of the Mongol Empire. This study aims to analyze the individual and collective roles of Kereyit figures, highlighting the religious and cultural diversity of the Mongols and offering a new perspective on medieval Eurasian history. In this regard, the topic will be approached through an interdisciplinary lens, encompassing both historical and cultural dimensions.
