As EMT said the Byzantines were a continuation of the Imperium Romanum, but as a Civilization they were a distinct entity. They were the medieval Greek-Roman Empire and they created large parts of what we consider Greek culture. They were a great civilization but putting them in the Vanilla game wouldn't be a good idea. We already have Rome, Greece and even the Ottoman Empire( which is the Muslim continuation of the Roman Empire). The Byzantines deserve to be in Civ5 but not in Vanilla, they should be added in the first or second Expansion pack. As much as I like the Byzantines ( they were my favourite civ in both Civ3 and Civ4), it would unjustified to have them in the Vanilla release and leave out Spain or Persia.
Also wasn't this thread about modding Byzantium in and not about whether they should or shouldn't be in Civ5?
Ugh the Ottoman comment is so wrong because Byzantium was Rome... they did not come in and conquer or change Rome, they were the part of Rome that didn't fall in 476. In fact Rome didn't fall in 476, it fell in 1453.
Russia, Holy Roman Empire, and other nations all declared themselves to be Roman too... Just because the Ottomans said it doesn't mean they were.
I don't think Byzantium is good for Vanilla because although they had a huge impact, they were Rome... You cannot deny that. A chunk of the Roman Empire survived on for 1000 years more. In fact it is in my opinion that Constantine's moving the capitol from Rome/Milan to Constantinople is what doomed the West to fall anyways.
Yes, Byzantium was different but take England for example, over time there language has changed a little, they went from Catholic to Protestant and their military today doesn't look anything like their military back in the early days. Someone from 20th Century England would not look English to someone from 900 AD and vice-versa.
I always thought that it would be neat to have Civ treat Rome differently and allow Rome to become "Byzantine" as they advance into the Middle Ages or just do what they are doing now and have them come in an expansion. It is just wierd to play Byzantium on Civ III or IV and not get Legions as well as play Rome without Cataphacts.
Justinian is the face of Byzantium... other possible leaders are Constantine, Basil II, and Irene.
P.S. off topic I never did understand why HRE made the game and not Austria. I thought Austria should have been stuck in to represent the Hapsburgs and HRE of later age while Germany represents Prussia and the later German Empire.
When I did a full civ map (Did Earth map with all civs at start)... I stuck HRE in Austria to be Austria since that area was blank and stuck Ottomans (which I renamed Turks) in Central Asia where the Turks are really from. Calling the Turks Romans is an insult since they murdered most the Greeks and Romans in Turkey.