<P> Sino - Roman relations comprised the mostly indirect contact, flow of trade goods, information, and occasional travellers between the Roman Empire and Han Empire of China, as well as between the later Eastern Roman Empire and various Chinese dynasties . These empires inched progressively closer in the course of the Roman expansion into the ancient Near East and simultaneous Han Chinese military incursions into Central Asia . Mutual awareness remained low, and firm knowledge about each other was limited . Only a few attempts at direct contact are known from records . Intermediate empires such as the Parthians and Kushans, seeking to maintain lucrative control over the silk trade, inhibited direct contact between these two Eurasian powers . In 97 AD, the Chinese general Ban Chao tried to send his envoy Gan Ying to Rome, but Gan was dissuaded by Parthians from venturing beyond the Persian Gulf . Several alleged Roman emissaries to China were recorded by ancient Chinese historians . The first one on record, supposedly from either the Roman emperor Antoninus Pius or his adopted son Marcus Aurelius, arrived in 166 AD . Others are recorded as arriving in 226 and 284 AD, with a long absence until the first recorded Byzantine embassy in 643 AD . </P> <P> The indirect exchange of goods on land along the Silk Road and sea routes included Chinese silk, Roman glassware and high - quality cloth . Roman coins minted from the 1st century AD onwards have been found in China, as well as a coin of Maximian and medallions from the reigns of Antoninus Pius and Marcus Aurelius in Jiaozhi in modern Vietnam, the same region at which Chinese sources claim the Romans first landed . Roman glassware and silverware have been discovered at Chinese archaeological sites dated to the Han period . Roman coins and glass beads have also been found in Japan . </P>

Who prevented the romans from sending embassies to the chinese