Between the Roman Empire and the Han dynasty, as well as between the later Eastern Roman Empire and various successive Chinese dynasties, there were (primarily indirect) contacts and flows of trade goods, information, and occasional travelers. These empires inched progressively closer to each other in the course of the Roman expansion into ancient Western Asia and of the simultaneous Han military incursions into Central Asia. Mutual awareness remained low, and firm knowledge about each other was limited. Surviving records document only a few attempts at direct contact. Intermediate empires such as the Parthians and Kushans, seeking to maintain control over the lucrative silk trade, inhibited direct contact between the two ancient Eurasian powers. In 97 AD, the Chinese general Ban Chao tried to send his envoy Gan Ying to Rome, but Parthians dissuaded Gan from venturing beyond the Persian Gulf. Ancient Chinese historians recorded several alleged Roman emissaries to China. The first one on record, supposedly either from the Roman emperor Antoninus Pius or from his adopted son Marcus Aurelius, arrived in 166 AD. Others are recorded as arriving in 226 and 284 AD, followed by a long hiatus until the first recorded Byzantine embassy in 643 AD.
The indirect exchange of goods on land along the Silk Road and sea routes involved (for example) 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 (Roman emperor from 286 to 305 AD) and medallions from the reigns of Antoninus Pius (r. 138–161 AD) and Marcus Aurelius (r. 161–180 AD) in Jiaozhi (in present-day 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 (202 BC to 220 AD). Roman coins and glass beads have also been found in the Japanese archipelago.