During his reign as Emperor, he led the Han dynasty through its greatest territorial expansion. At its height, the Empire's borders spanned from the Fergana Valley in the west, to northern Korea in the east, and to northern Vietnam in the south. Emperor Wu successfully repelled the nomadic Xiongnu from systematically raiding northern China, and dispatched his envoy Zhang Qian into the Western Regions in 139 BC to seek an alliance with the Greater Yuezhi and Kangju, which resulted in further diplomatic missions to Central Asia. Although historical records do not describe him as being aware of Buddhism, emphasizing rather his interest in shamanism, the cultural exchanges that occurred as a consequence of these embassies suggest that he received Buddhist statues from Central Asia, as depicted in the murals found in the Mogao Caves.
