das
Regeneration In Process
I have my althist to finish. You write it! 

And the Chinese Emperors had...wait for it...the Mandate of Heaven. And the Byzantine Empire was seen as favored by Jesus and God.North King said:God-Emperor should come later, when the thing is coming to an end--divine empires tend to fail, because each mistake is seen as a contradiction of the authority of the "god". The Emperor can last plenty long, anyway--a nice 800+years for the Byzantine Empire, and, admittedly with intermittent breaks, 4000 or so years for the Chinese Empire.
In ancient times, the number of gaps between the various continents water-wise will mean they will, indeed, have to develop superior naval technology, and land technology will conversely fail to be quite as developed as OTL ancient times. Engineering and such domestic things--well, the civilizaionts develop in a fairly nice area; no real need to transport water long, long distances, and roads are fairly useless, the only avenue I'd say architecture would be truly developed is in monumental buildings. Given the naval nature of things and the lack of large challenges on land that can burn down many cities at once, we could actually see a "wonder culture," where cities compete to get the biggest and best new wonder.
In classical to medieval times, as the kingdoms solidify and coalesce on the mainland, land technology will try to catch up, but at the same time, population pressures could drive the steppe nomads from the west into the Peninsulas, greatly hindering economic efforts. They will have to face both scattered raids from the barbarians, and large scale invasions, thus feudalism is plenty likely to develop there, just like it did in ours, and feudalisms tend to disrupt growth...
Meanwhile, in the north, the medieval age will be more the dark age, as the various river valleys, lakes, and forests are divided between petty kings, fighting for control to unify the whole--on occasion, a unified dynasty arising, but not sustaining themselves--it is pretty much out of the running for world power.
Other nations of the Mainland
the Empire sees fit to actually invade the nations on the Mainland itself, and since they are still in their formulative stage, economically woefully underpowered, and surrounded by willing allies of the Empire, one by one they are subjugated.
As the industrial age is entered, the denizens of the Empire have formed a multi-national state, rather like the modern United States in that it manages to put aside nationalism in the name of patriotism, and they begin to sponsor wars on the mainland, and against the nations of the other continents that are left--a few on the periphery of the Eastern Continent, and the South Western one (the one directly south was easily taken over entirely by the Empire).
Given the overwhelming superiority of the Empire, they won't try developing a nuclear weapon--no motivation, and other civilizations simply won't have the proper infrastructure. Thus, no nukes. But a plethora of tanks, armored vehicles, machine guns, artillery, chemical weapons--in short, things which can kill a lot of local miscreants in a short time, yet relatively in expensive.
The Empire will have to have a large religion
das said:Quite agreed, but there would be a need to defend from the barbarians (as the sea-based civilizations - in the Gulf, anyway - will be too busy waging their naval wars to launch any serious overland punitive expeditions). This world may see lots of "great walls".
I rather doubt that land technology will really catch up - most of the development in that field during the Middle Ages concerned cavalry and artillery, both of which are of little use for civilized powers. Also, how are such raids damaging to economy? Sea powers are likely to be of the more commercial mind, though I could imagine damage being caused to the agriculture.
The steppe nomads won't bring on any dark age in this world, I suspect. But from the north of the Gulf, pirates/raiders (Viking-like) might do just that. Certainly they would disrupt commerce greatly. Thankfully, the Home Island will indeed be shielded from them by its future enemies (btw, maybe this is the point at which it will attain independence - after sea barbarians disrupt communications with the home empire?)...
Rather unlikely, I don't imagine any sort of large empires arising there. Pirate/raider tribes, however, will quite easily fit there and terrorize much of the Gulf.
Of particular interest is the western region; the Gulf will mostly be dominated by the Empire even in the earlier parts of modern history, but in the west a different civilization will arise, possibly even building a large empire that will become one of the leaders of the Last Coalition.
The Gulf it will quite easily take over, except perhaps the west and the far north (btw, in this world there might actually be some modern-day barbarians, especially in the far north; its unlikely that anyone will bother conquering them, and that might lead to some interesting developments, so lets leave them). But IMHO further west is unlikely to be conquered - its too large and far-flung, and doesn't seem awfully profitable.
The small Inner Ocean islands and the direct Southern Continent will be taken over quite easily; the southwest will probably see a drawn-out struggle in the jungles. Actually I think it is a more opportunate site for a China-like civilization in the center. Most civilizations in this world seem to be Mediterranean, Viking or Chinese, interestingly enough. Not sure where did I see such a combination before... Settlers?
The Eastern Continent, however, is likely to be a home of an Egyptian civilization, that is likely to become one of the Empire's first victims outside of the Mainland.
Some thoughts on modern technology:
1. No nukes indeed.
2. I doubt that there would be tanks - the Empire's quest for global supremacy is unlikely to bog down in trench warfare, the world just doesn't fit for it, and so there will be no need for tanks.
3. Artillery is also rather slow and takes up much space. The best artillery in this world will be naval and coastal, ofcourse.
4. Aircraft carriers, however, would be a godsend for the Empire. These, along with aviation, would advance ahead of time. I could imagine the Empire developing a doctrine not unlike the modern American one, with aeronaval task forces and special forces being employed as a quick, effective and intimidating method of putting down rebellions and upstart weaker rulers.
Actually, no. Religiously I think it will be best off as Rome - religion, at first anyway, would not be too important, there wouldn't be any real fanaticism, and foreign religious elements will be integrated.
Later on, something like the Cult of Mithras (with some elements of Poseideon, ofcourse) will appear - it would really fit this Empire, much better than OTL Rome. The Emperor (how ever divine) would, much like in Japan, become ever more a figurehead, with the military elite dominating the government. The Cult of Mithras is perfect for a military junta, as it implies a Mason-like organization within the army, so the army becomes a state within a state. But ofcourse not all will like it; in fact it is best if by the time of the NES there is a growing anti-military movement, possibly divided into an atheist-secularist movement and a one united around some new religion.
North King said:Cleric: Probably less so than in our world, due to the sheer power of the government.