Yes, I've heard about the lame voice-acting, one-dimensional quests, and ridiculous auto-leveling that equalizes every forest bandit with your Daedric longsword. The nitpickers of this frankly ludicrously vast game are legion, and not necessarily wrong - the Rumare Slaughterfish quest being emblematic of every flaw this game has. I get it. Regardless of any shortcoming this game has, the draw, for me, as a history buff is that it does better than any game before of approximating life in a medieval empire; a world of vastly different landscapes, cultures, and languages, all united by a common, shining capital. A world where the Emperor is more than just temporal authority, but commands the religious souls of each denizen of his empire. A world where armed revolt is always simmering just below the surface, and jaunty rogues with an agenda all of their own can rile up the local populace with ease - where allegiance goes no further than the strongest landowner in the area.
A place where crumbling, pagan ruins dot the countryside - a place that is the inheritor of a tradition thousands of years old, so far removed from its origins that their institutions survive on inertia alone. The experience of playing in this kind of world is not limited to Oblivion; the reality of being there was a burden that the Byzantine Empire bore for over a thousand years. Anyone wishing to be transported to a time and place like that of Oblivion need do no more than read a book by the noted Byzantine historian Donald Nicol. Byzantium is Tamriel, by design or by accident.
Oblivion takes place in the central empire's province of Cyrodiil. This province is marked by verdant hills and rolling forests, with whitecapped mountains in the north and a near-impregnable capital city situated on an inland lake in its centre, which has withstood centuries of siege by enemies without once falling. Sound familiar? Sounds a hell of a lot like Thrace to me. Constantinople withstood siege by the Arabs for over five hundred years, in part due to its highly defensive location and naval use of Greek Fire. Thrace itself is bounded to the north by the Rhodope Mountains, and to the south by the Aegean Sea, and formed the agricultural heartland of Byzantium. Constantinople needs no introduction as a stand-in for Cyrodiil's Imperial City; a place where every culture from the corners of the empire converge to pray, plot, and engage in commerce.
Everywhere one travels in Cyrodiil, one stumbles upon the ruins of ancient pagan chapels and temples (it should be noted that Tamriel has not yet made the conceptual leap to monotheism). They may worship a different God or Goddess of old, yet the graceful arches, sublime columns, and intricate marblework all point to a centrally organized belief system a thousand years in the past. This is no different than Byzantium, where the average citizen would have been aware of dozens, if not hundreds of ill-understood, crumbling religious ruins whose rubble dotted the landscape. A temple or shrine to this or that God, a place of worship deep in the woods to a pagan Goddess whose name is lost to the mists of time. The people of Byzantium lived deeply aware of the sheer history their land held, and the mystery of it, much like for the inhabitants of Cyrodiil, was frequently alluring yet confounding at the same time.
Best as I can tell, Tamriel seems to be governed by a series of feudal fiefs, each controlling a commune and its immediate environs. Law and order, within town walls, is subcontracted to whatever Duke or Lord holds power there; but highway patrols on otherwise unassigned land seem to be run by Imperial guards in the name of the Emperor. This is a state of affairs not unique to Byzantium, but best exemplified by it; through its use of Exarchates and the Thematic system, the emperors in Constantinople continually subcontracted military and political power to powerful landowners in the provinces, much like in Cyrodiil, but guaranteed (best as they could) passage through the old Roman roads that crisscrossed their territory.
One striking feature of Tamriel, like in Byzantium, is that the emperor represents both the temporal and spiritual centre of the empire. While he has his spiritual advisers (much like the Patriarch of Constantinople), the Emperor is understood to be the embodiment of the "perfect man", and to carry out his role as leader with the tacit approval of God. The Byzantines believed that no mutilated man could be Emperor, for he would not be made in God's image; hence the proliferation of mutilation that occurred with each succession struggle, of which there were many during the seventh and eighth centuries. Justinian II bucked this trend in 705 upon his re-ascension to the Imperial dignity, despite having his nose cut off, but ritual mutilation of would-be pretenders to the throne continued even to the late 14th century, when John V had his son Andronikos III blinded in part to prevent possible usurpation.
Cyrodiil, despite being at the heart of the empire, forms a melting-pot of different ethnicities, be they Nord, Elvish, Angorian or Khajiit. Byzantium, and Constantinople in particular, would have been no different. Bulgars, Gothic Tribes, Syrians, and Italian merchants all found a home in the capital, each one bringing a different skill and threat level to the game of empire. And while Greek, like Imperial in Oblivion, was the preferred culture of empire, it was by no means the exclusive one, though its leaders were, by and large, pasty white men. Some things never change.
Primogeniture strikes me as an element in Cyrodiil that is given a lot of lip service, and nothing more, like in Byzantium. Your main quest is to find the illegitimate son of the emperor, so that his Imperial lineage may be continued; but like in any empire during an interregnum, pretenders to the throne are many, and should the Favoured Son be recalcitrant, the law of might will win out in the end. Hellish ghouls add a refreshing element to the succession battles in Cyrodiil, but the rubric remains the same. That said, the practice of recruiting culture-specific Lords to rule over their own dominions in the name of a faraway emperor is more reflective of Ottoman empire practice than Byzantine. But still. Same capital city.
This entire writeup was inspired by an image I had in my head, of dockhands in Selymbria loading up a ship with wheat headed towards the shining city of Constantinople, a city most of them will know only from legend; a place that is at once a tangible location and unattainable myth. It brought to mind memories I had of the hundreds of hours I spent playing Oblivion; hours spent discussing rumours about the capital with faraway innkeeps, finding dubious imperial heirs, and debating cultural irredentism with Nords. To me, the richness of Oblivion lies not in the formulaic quests it offers, but of the total immersion into the daily life of a Medieval empire, one whose closest approximation is the realms of Byzantium. Rowdy cultural-specific inns past sunset; trigger-happy municipal guards; hermits living self-sufficiently amid crumbling ruins deep in first-growth forests. All find a home, however awkward, under the Emperor, and these vicissitudes of Imperial life all find a vignette in this game, and in the greater sense, in the Byzantine Empire which most closely approximates Tamriel. This, for me, is the magic of history - and maybe for you, too, and if it takes a video game to feel it - so much the better.