He was emperor of both east and west, but he got rid of the tetrarchy, but he kept Diocletian's notions of these smaller provinces going into diocese, going into prefects. So you have that continuity, but then later on, in the mid-7th century, it was turned into more of a feudal theme system in the Byzantine Empire. Once again, this was under Heraclius, who also made Greek the official language. And the reason why I say it's feudal, it was comparable to the feudal system in Western Europe at the time, was that it provided land grants to local rulers in exchange for their military service and the ability for them to send resources up to the emperor. In terms of culture, you have many of the things that we associate with the Roman Empire. You have chariot racing. You have gladiator fights.