 imperial china had a long tradition of foreign relations. from the qin dynasty until the qing dynasty, the culture of china had an impact upon neighboring and distant countries, while gradually being transformed by outside influences as well. ==background==  in premodern times, the theory of foreign relations of china held that the chinese empire was the celestial dynasty, the center of world civilization, with the emperor of china being the leader of the civilized world. this view saw china as equivalent to "all under heaven". all other states were considered to be tributaries, under the suzerain rule of china. some were direct vassals. theoretically, the lands around the imperial capital were regarded as "five zones of submission", - the circular areas differentiated according to the strength of the benevolent influence from the son of heaven. there were several periods when chinese foreign policy took on isolationist tones, because of the view that the rest of the world was poor and backward with little to offer. nevertheless, china was a center of trade from early on in its history. many of china's interactions with the outside world came via the silk road. this included, during the 2nd century ad, contact with representatives of the roman empire, and during the 13th century, the visits of venetian traveler marco polo. chinese foreign policy was usually aimed at containing the threat of so-called "barbarian" invaders (such as the xiongnu, mongols, and jurchen) from the north. this could be done by military means, such as an active offense (campaigns into the north) or a more passive defense (as exemplified by the great wall of china). the chinese also arranged marriage alliances known as heqin, or "peace marriages." chinese officers distinguished between "matured/familiar barbarians" (foreigners influenced by chinese culture) and "raw barbarians". in many periods, chinese foreign policy was especially assertive. one such case was exemplified by the voyages of the eunuch admiral zheng he during the ming dynasty. ==qin dynasty==  although many kings of the shang and zhou dynasties ruled beforehand, in 221 bc, the ruler of the state of qin, qin shi huang, was the first to conquer the different nations of the zhou confederation, as well as 
Foreign_relations_of_China History_of_Imperial_China History_of_the_foreign_relations_of_China