Zhang Qian in the context of "Silk Road"

Emperor Wu of Han (156 – 29 March 87 BC), personal name Liu Che and courtesy name Tong, was the seventh emperor of the Han dynasty from 141 to 87 BC. His reign lasted 54 years – a record not broken until the reign of the Kangxi Emperor more than 1,800 years later – and remains the record for ethnic Han emperors. His reign resulted in a vast expansion of geopolitical influence for the Chinese civilization, and the development of a strong centralized state via governmental policies, economical reorganization and promotion of a hybrid Legalist–Confucian doctrine. In the field of historical social and cultural studies, Emperor Wu is known for his religious innovations and patronage of the poetic and musical arts, including the development of the Imperial Music Bureau into a prestigious entity. It was also during his reign that cultural contact with western Eurasia was greatly increased, directly and indirectly.

During his reign, Emperor Wu 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.

The foreign relations of Imperial China from the Qin dynasty until the Qing dynasty encompassed many situations as the fortunes of dynasties rose and fell. Chinese culture had influenced neighboring and distant countries, while being transformed by outside influences as well as being conquered. During the Western Han dynasty, the Silk Road trade routes were established and brought Hellenistic Central Asia, Persia under the Parthian Empire, and South Asia into contact with the Chinese empire. During the 2nd century BC, Zhang Qian became the first known Chinese diplomat to venture deep into Central Asia in search of allies against the Mongolic Xiongnu confederation. Han Chinese attempts were made at reaching the Roman Empire and although the mission led by Gan Ying in 97 AD was a failure, Chinese historical records nevertheless maintain that the Romans traveled to southern China and Vietnam via the Indian Ocean. Buddhism from India was introduced to China during the Eastern Han period and would spread to neighboring Vietnam, Korea, and Japan, all of which would adopt similar Confucian cultures based on the Chinese model.

Following the fall of Sasanian Persia to the Rashidun Caliphate, Chinese contacts with the Islamic world were initiated during the Tang dynasty. Foreign faiths entered China at this time, such as Zoroastrianism, Nestorian Christianity and Islam, although Chinese Buddhism and Taoism remained prominent. The Song dynasty dealt on a basis of equality with the neighboring Liao and Jin dynasties until falling to the Mongol conquest. The Mongol Empire became the dominant state in Asia, and the Pax Mongolica encouraged trade of goods, ideas, and technologies from east to west during the early and mid-13th century. Marco Polo could safely travel back and forth, for instance. The Mongol-led Yuan dynasty founded by Kublai Khan ruled from the capital of Khanbaliq (modern Beijing). The Yuan dynasty's failed diplomacy with the Kamakura Shogunate of Japan led to the Mongol invasions of Japan, which also ended in failure for the Yuan Empire.