The Roman Empire was very powerful, especially in AD 117, when they controlled most of Europe. The emperor was Julius Caesar. (I think there were more, but I can't be bothered to list all of them.) They were very civilised, at the time, and apparently knew how to keep order.
2. Reg - "Apart from the sanitation, the medicine, education, wine, public order, irrigation, roads, a fresh water system, and public health, what have the Romans ever done for us?"
When going to a new place, living in a new community or environment, one should respect and follow the customs, habits, regulations, or way of life of that place.
Example:
BF:Hey girlfriend,when in Rome, do as the Romans do
Boys who enjoy yaoi (a genre in Japan that contains sexual and/or romantic relations between two men); literally translates to "rotten boy"; corresponding female : fujoshi