What would happen if we don't have good citizenship then we would be all separated and would not get along. If we had good citizenship (like today) would get along easily and fairly.
Depends on Emperor, but mainly was the army. The army conquered many lands such as the land now called England. They even got as fair to Asia, before being pushed back. As well when conquering those lands, they gained Servus or slaves. That could then go to be a Tiro, or Auxilia. With all of that brought power and wealth. As well a lasting image of how terrifying the empire was.
There were many significant political changes which Diocletian enacted. One important thing which happened was that he divided the Roman empire into two parts. This meant Rome was being effectively taken care of by two different emperors at the time for that reason.
Natural elements of the ecosystem are often borderlands, for example rivers or mountains, the Great Lakes.
