This chapter is an overview of the extant Middle Mongolian historical sources of the Mongol Empire, its documents arranged here according to their places of origin, the writing systems used, and their content and genres. They are described and evaluated in the following sections: extant and lost chronicles, Uighur script epigraphic monuments (edicts, epitaphs and other memorial inscriptions, graffiti, seal and coin inscriptions), Uighur script letters of Mongol rulers to foreigners, monuments from Qara-Qoto, Uighur script documents from the lands of the Ilkhans and their vassals and from the Turfan area and the Dunhuang Mogao caves, square-script monuments, and badges and xylograph fragments in square script or in Uighur letters. The notes also offer new interpretations of some passages of the monuments discussed.

Tangut script textual and visual sources dating to the late twelfth century and the thirteenth (and beyond), though mostly Buddhist in nature, are promising materials for historians of the culture and politics of the Mongol Empire. The well-known Qara-Qoto collection housed in St. Petersburg, Russia, contains materials dating well beyond 1227, the year the Tangut Xia state fell to Mongol armies. Tangut Buddhist materials are particularly promising sources for the history of printing and religion in the Yuan dynasty. The chapter describes the origin, status, dating, and accessibility of the main collections of these sources. It then summarizes the state of research on these materials.

Chapter 4, “Black City” shifts from eastern and central to western Mongolia. It focuses on the only Great Yuan city for which administrative documents survive from the post-1368 period.Qara-Qoto or Black City is located in the southwestern corner of today’s Inner Mongolia. Saved from extinction by arid conditions and long centuries of neglect, the Qara-Qoto documents reveal that Great Yuan regional governance continued after 1368. Documents occasionally mention military mobilization against impending Ming attack, but most focus on daily governance. This may not seem exciting, but it reminds us that 1368 as a transformative moment was in part a narrative creation of the Ming court meant to change contemporary perceptions of both the Great Yuan and the Great Ming courts. The documents also reveal Chinggisid nobles’ ongoing importance to Great Yuan governance in Qara-Qoto and surrounding regions after 1368.