Foreign relations of imperial China
For the later history after 1800 see History of foreign relations of China. 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