Complex sentence: Following the opening of the Silk Road in the 2nd century BCE, the Chinese liked to think of the Roman Empire as a civilized pendant to the Chinese Empire, both occupying the extreme positions on the trade route, hence the "mirror" name.
Split into simpler sentences: Following the opening of the Silk Road in the 2nd century BC, the Chinese liked to think of the Roman Empire as a civilized pendant to the Chinese Empire. The Romans occupied one extreme position on the trade route, with the Chinese located on the other, hence the "mirror" name.