Since the Roman Empire started to expire in 180 base power down because it cannot rule the Empire is very spacious. Some early emperors shared must be appointed to a separate ruling the Empire.
Since 180 AD the Roman Empire began to decline jurisdiction. Because it can not rule the empire with a very large size. Some require a separate appointment to co-emperor ruled the empire.
Since 1975. 180 Roman Empire begins to deteriorate อำนาจล. Since can't ruled a vast empire, very. Some time to be appointed emperor in order to separate rule the Empire.