In an effort to forge alliances and expand France's geopolitical reach, King Louis IX dispatched Andrew of Longjumeau to the court of the Khagan of the Mongol Empire. This diplomatic mission was emblematic of the growing interactions between Europe and Asia during the 13th century, a period marked by the vastness of the Mongol Empire, which at the time was one of the largest contiguous empires in history. Andrew's journey was not merely a diplomatic overture; it underscored the strategic interests of European powers in establishing relations with the Mongol rulers, who controlled significant territories across Asia and posed both opportunities and challenges for trade and military strategy.

Andrew's mission involved meeting the Mongol Khagan to discuss potential alliances against mutual enemies and to facilitate trade routes that could benefit France. The meeting represented a pivotal moment in the broader context of cross-cultural exchanges, as both the Mongols and the Europeans sought to learn from each other's military and administrative practices. The visit was fraught with challenges, particularly as the Mongols maintained a complex web of alliances and hostilities with various entities within Europe and Asia. Nevertheless, Andrew’s role as an ambassador highlighted the willingness of European leaders to engage with the Mongol powers for mutual benefit.

While Andrew of Longjumeau's mission ultimately did not lead to immediate or lasting alliances, it reflected the curiosity and ambition of European monarchs during this era, who were beginning to understand the implications of global diplomacy. The meeting between Andrew and the Khagan was significant in that it established a precedent for future interactions between the West and the East, laying the groundwork for continued diplomatic relations. The results of this mission would resonate across Europe, as news of the Mongol Empire's strength and culture began to reach the courts of Christendom, altering perceptions and strategies regarding trade and warfare.