I just found this excellent reference website.
If you follow it thru you can get a feel for the rise of the Byzantine 'superpower', and its gradual fall, due to a variety of factors. It took 1100 years in Byzantium's case, but with the speed up brought by modern technology, we should expect the rise and fall of the West to be much shorter (unless it is able to learn the lesson from history and stop it).
You can also see how Islam came banging on the door of Constantinople over 800 years, and eventually broke in. And you can see the collapse of the Roman empire, relative to events in Byzantium.