Given textual and archaeological evidence, it is thought that thousands of Europeans lived in Imperial China during the period of Mongol rule. These were people from countries traditionally belonging to the lands of Christendom during the High to Late Middle Ages who visited, traded, performed Christian missionary work, or lived in China. This occurred primarily during the second half of the 13th century and the first half of the 14th century, coinciding with the rule of the Mongol Empire, which ruled over a large part of Eurasia and connected Europe with their Chinese dominion of the Yuan dynasty (1271–1368). Whereas the Byzantine Empire centered in Greece and Anatolia maintained rare incidences of correspondence with the Tang, Song and Ming dynasties of China, the Roman papacy sent several missionaries and embassies to the early Mongol Empire as well as to Khanbaliq (modern Beijing), the capital of the Mongol-led Yuan Dynasty.
Mainly located in places such as the Mongol capital of Karakorum, European missionaries and merchants traveled around the Mongol realm during a period of time referred to by historians as the "Pax Mongolica". The most famous European visitor to China during this period was Marco Polo, preceded, respectively, by his father and uncle Niccolò and Maffeo Polo. Perhaps the most important political consequence of this movement of peoples and intensified trade was the Franco-Mongol alliance, although the latter never fully materialized, at least not in a consistent manner. The establishment of the Ming dynasty in 1368 and reestablishment of native Han Chinese rule led to the cessation of European merchants and Roman Catholic missionaries living in China. Direct contact with Europeans was not renewed until Portuguese explorers and Jesuit missionaries arrived on Ming China's southern shores at the beginning of the 16th century, during the Age of Exploration.