I'm following and Liking this. I had some vague hope of a reconciliation between the Eastern and Western rites, but that really had little basis; Hungary, insofar as it remained unified with Constantinople on any terms, would indeed be most likely to shift toward Eastern Orthodoxy. Given that, it seems the best case for both Empire and Hungary as a portion of the Empire to be under a single Imperial crown rather than the spin-off toward a younger brother cadet line the earlier Emperor wanted, so it is just as well this came to nothing. I presume the Dalmatian coast is thus firmly under the "Rhomanian" imperial scepter?
(I am not sure by the way whether "Rhomanian" is any less artificial an OTL modern neologism than "Byzantine," which I am more comfortable with, but I do realize the latter has perjorative and offensive aspects from the point of view of the loyal subjects and rulers in Constantinople, who did not take kindly to being called "Greeks" either despite their deep Hellenization--they were "the Romans" to themselves pure and simple, and the fact they didn't rule the city of Rome itself nor control the Roman Pope was something that irritated them and that they'd contemplate rectifying forcibly if they judged themselves strong enough in Italy to do so. We say "Rhomanian" with an h today to distinguish from modern Romania, and because it seems weirder and more confusing to us to notice that Rome the city is on alien and hostile territory to them so we boggle at saying "Roman" and being done with it. There is no pleasing everyone, I know "Byzantine" is to take their Latin foes' side, so I guess I am stuck with "Rhomanian." Can we shuffle the linguistic deck again and say "Rhoman?" I'm going to try that and see if I get shot down in flames for it!)
Dalmatia might be problematic if the Italian-dialect speaking citizens of the various merchant city states there happen to lean strongly toward Rome in religious rite, so that pressure to align with Rhoman orthodoxy (hmm, that's problematic, but I'll keep rolling with it) does not result in simple compliance with some grumbling. Of course it has already been remarked that the pragmatic and politic ruling dynasty subordinates ideological and sectarian neatness to interests of state, and so it is always possible for Rhoman policy to shelter a minority of subject territories that still look to the Roman Papacy, or for that matter on paper anyway some third rite could also be tolerated. (In fact, while I gather Rhoman policy hitherto has worked to uproot and expel Islamic influences, that too could be revised and the Orthodox Emperor of whatever dynasty tolerate ongoing Muslim practice in some regions, in the future if not yet). Both though have the obvious problem; probably it is wrong in any era whatsoever to totally discount sectarian religiousity as a relevant political factor, and certainly in this age it is a major one. Latin rite subjects of "Rhome," and Muslim ones, will in fact have a real tendency to turn toward alien political patronage and form a dangerous political fault line these exterior foes can try to exploit. "Tendency" means that by no means is a Roman Catholic or Muslim who is nevertheless perfectly loyal to Constantinople, and active and zealous in upholding the Eastern Empire, a contradiction; they can easily be the majority and actively assist in rooting out and dealing with the traitors among themselves. But it certainly puts a cloud of doubt over all of them, and that cloud will tend to veer Imperial policy against trusting them, which will feed back in eroding the loyalty of such subjects. Generations and centuries of proven loyalty, and the Rhoman system being a strong one which makes it advantageous to adhere to, and even attracts factions outside the border to seek Imperial favor rather than strive to undermine it, could dispel such doubts...but I would think, again considering that sectarian religious identity has secular and political aspects, that such citizens would tend to convert to the ruling orthodoxy after all, which would eliminate all (well most, ask after the fate of the Spanish subjects who converted from Judaism and Islam to see how doubt and persecution can still continue!) the division.
But it is not clear to me where Dalmatian citizens stood in the East-West split around this time anyway. I am following another TL that focuses on Hungary and Dalmatia in this period on quite a different tack (this Hungary is firmly on the Latin side, as is the strengthened Dalmatian confederation under that Magyar dynasty, and I wonder whether that version of Hungary shall succeed sooner or later in taking the Western Holy Roman Imperial crown and thus projecting the Latin rite farther east and south--at this point in the TL "Rhome" is still standing pretty strong and of course on OTL time scales direct confrontation with strong Islamic powers is still centuries in the future). In that TL, it seems at least the northern tier of Dalmatian cities are quite Latin in rite, but the author might be glossing over ambiguities or I might have failed to take proper note of them.
I seem to recall that OTL, prior to the 13th century we are now well into, even Venice despite its proximity to Latin power bases, veered Orthodox, due to the city early on becoming an exarchate of Rhoman power and later, when that power ebbed but remained strong, seeking favor with it for the sake of trade opportunities in the Rhoman sphere. Under these ATL circumstances, perhaps Venice too plays both sides off against each other and remains ambiguous? If so, the entire Adriatic coast, its Italianized trading towns, from Greece all the way into Venice, is in play. Given that Ottokar was said to have holdings "reaching to the Adriatic" prior to his failed bid to seize Hungary, I don't know if that refers to Italian towns on the northwestern Adriatic but south of Venice, having the temporary overlordship of Venice itself, or reaching east further some claims on the northern Adriatic reaching into Istria, perhaps Trieste. Again I'd think somewhere south of Venice's own holdings, perhaps the next rival power to the south, sectarian allegiance goes firmly to Rome, but then again possibly some city states scattered all down the Italian coast of the Adriatic lean toward Constantinople too, both as relics of a stronger Rhoman presence earlier and current vested interests in access to Rhoman trade.
It does seem that "Styria," whatever exactly that means in this age, would be firmly Latin, and so on up to Vienna. So, basically the Crown of St Stephen, perhaps now annexing Trieste, perhaps with Trieste being the southeastern salient of Latin allegiance, but Slovenia, Croatia, Bosnia and Serbia as well as coastal Dalmatia, is going firmly Orthodox, a process accelerated by the Latin-partisan dissidents outing themselves and being undercut, discredited, executed, exiled or forced to profess conversion, consolidating all these realms firmly into the Orthodox sphere. Going northward, the line dividing the spheres will follow the Austrian-Hungarian border and Slovakia, as OTL, included on the Orthodox side. Thus greater Hungary, an increasingly Orthodox bulwark, incorporating Slovakia, reaches up to Bohemia-Moravia proper, which is firmly Latin rite, and thence I suppose the border runs along the OTL Slovak-Polish border more or less.
Now here's a thought.
I was greatly puzzled by this:
1285- A second large invasion of Hungary by the Mongols occurs and though destructive is not nearly on the scale of the 1241 invasion. Roman military tactics during the intermittant period had greatly improved to counter nomad horseback armies effectively. A second reconstruction program is started and the process of cultural shift continues. Melkite Othordoxy is increasing in Hungary and Greeks are the main source of settlers for repopulation of the countryside.
So hang on, I thought an accord with the Ilkhanate had been reached. I infer that "Ilkhanate" refers to a portion of the Mongols who are splintering into successor realms, and this Mongol invasion comes from another bunch of Mongols who are I suppose based in Ukraine and Russia further north, and have come to a political parting of the ways with their Ilkhanate cousins to the south. I would guess the division lies between the Black Sea and Caspian somewhere, the Ilkhan holding whatever is not under firm Rhoman control south of that line--IIRC, unless I am mixing up other TLs, Rhome holds the Crimean peninsula and is of course the supreme naval power by far on the Black Sea, and of course holds Thrace and into and perhaps beyond OTL modern Bulgaria--at what point on the west coast of the Black sea Imperial power fails is not clear to me, but I gather that whatever lies beyond, over to the narrow isthmus the Empire holds to secure the Crimea, is northern Mongol more or less, and we might say, Russian shading into Baltic--that is, Estonian-Finnish, Latvian and Lithuanian and Polish.
At this early date, both branches of the legacy of Genghis Khan's conquests are neither Christian nor Muslim; their empires each have a certain tolerance for many rites, but we are told the Ilkhans were leaning Nestorian Christian before the current Emperor's sister married into the Khan's family and perhaps has been tweaking either a shift to full Orthodoxy or a possible sectarian detente welcoming in the Nestorians.
Now, given the salience of religion in politics and that the northern Mongols probably find it expedient to discredit and contradict their Ilkhan cousins at every opportunity, the better to shore up their own claims for supremacy, I think it might not be strange if, before the Mongol system breaks down in Russia, for the northern faction to lean toward Latin rite missionaries just to spite their southern rivals. Kiev had already gone Orthodox of course, but perhaps under ruthless enough Mongol rule, even Ukraine might be converted. A more likely course I think is that this conversion happens with fewer hitches in the farther north, the White Sea and Novgorod and Muscovite Russians Romanize fast and thoroughly, while the prior layer of Eastern rite orthodoxy in Kievian Rus might make the populace resistant and form a rallying cry for anti-Mongol resistance. If Rhom exploits this, we could conceivably have either a series or single Kievian-Ukranian client state fostered by Rhoman power on the Black Sea and with Ilkhanate connivance, or possibly annexation of much of south Ukraine and the Volga mouth feeding in to the Black Sea region annexed outright as themes of the Empire, closing the loop of Rhoman hegemony around the Black Sea by joining up to the Georgian client state in the Caucasus.
In reaction to this, North Mongol flirtation with the Latin Rite could well solidify, leading to baptism of a Mongol dynasty into the Roman Catholic church. In the longer run, this means that the line dividing Slavic peoples between Orthodox and Catholic spheres runs more east-west and divides them north and south, leaving Czechs, Moravians, various minorities such as the Sorbs absorbed into German and other Slavic identities OTL, the Poles, Lithuanians and Latvians united with the northern Russians of OTL. It is actually my impression that OTL, were it not for the sharp confessional division clearly separating Poles from Russians, this divide would be much more soft and ambiguous--that Polish and Russian as languages for instance are fairly close to one another. Fusing everything north of Rhoman grip out of the Black Sea and Hungary into the Latin sphere would leave the non-Ukrainian Rus identity as appearing to be a branch of Polish, or vice versa.
Meanwhile aside from a foundational conflict with their Orthodox cousins to the south under Rhoman protection, or even subsumed into the empire directly, to the west the Poles face Germans and Czechs, and to the north across the Baltic, the various realms of Scandinavia. The fate of the Finns is unclear to me, whether they would form another nation, or be subjugated in the same category as the Sami by Swedes, Russians, Hanseatic Germans or all three.
What happens after that depends on whether the Hungarian dynasty lays foundations for indefinite survival of the Eastern Empire. I see the core of this empire being Anatolia and the Balkans, plus the entire shoreline of the Black Sea--Hungary itself secures most of the length of the Danube and surrounding valley to the Carpathian mountains I suppose. We have the Caucasian bulwark as a client kingdom, currently Georgia, and that leaves the northern shore of the Black Sea as a soft zone that the Empire must pour some resources into because it has little natural defense against steppe nomad waves. But I think if that imperial core can be sustained it provides enough wealth and manpower to keep aiding this zone, whether as a client kingdom or set of them or as outright provinces, and the flip side of making that effort is that Ukraine so defined and extended east (possibly being of less extent northward) is itself, if defended, a rich set of territories to contribute to overall Imperial strength. Such an empire, if it avoids going into severe political tailspins, can probably hold. Latin Europe, instead of being threatened by an expansive Ottoman type Islamic empire, instead faces an Orthodox empire. This may serve to define an apparently Hapsburg HRE much as the defense against the Ottomans shaped the Austrian Hapsburg empire OTL.
It is up in the air whether the Rhoman core can buff itself up by holding any of Mesopotamia, the Levant, Egypt, or the Maghreb. By this date, north Africa west of Egypt itself is Islamic, Egypt teeters on the edge of its Coptic population converting, the Levant is mostly Islamic but also home to a great many sectarian heterodoxies (due to its highlands offering many bastions). The Crusader kingdoms have been at least partially saved already, and by Rhoman efforts backstopping the "Frankish" Latin Crusaders. Note that OTL, the Latins were keen to eliminate Constantinople's influence despite the fact that it was a pact between the Popes and the Eastern Empire that prompted the First Crusade in the first place. The Venetian backed conquest of Constantinople and Latin Empire have been butterflied away for the moment anyway, but the allegiance of the Crusader realms of "Outremer" is not entirely clear here; they need Rhoman power, this we know from OTL, but any realms run by Latin-leaning lords might not fully realize that. Or the manner in which the Rhomans have taken charge might be proof against Latin subversion, perhaps by luring or forcing conversion to the Eastern rites and loyalties despite the Western origins of the Crusaders.
So for the moment, the Ilkhans are conceded Mesopotamia, and despite their Christianization, I doubt that the Eastern Empire will ever be able to hold that territory on a lasting basis. The Mongol rulers might be Christian in a rite that anyway is allied to the Rhoman one, but the populace they rule is probably going to be slow to convert. In the Levant however, there is so much heterodoxy I guess an astute Imperial policy can keep the upper hand there, if not by direct rule than by a suitable mix of client states.
If the Empire can hold the Levant and Egypt, or even just one of these, in future generations it can power project via the Red Sea into the Indian Ocean. Otherwise, doubting as I do any stable conquest of Mesopotamia, they are confined to the Eastern Med and Black Sea. Which is really quite a lot!
I doubt very much Islam and powerful Islamic states are down for the count. There has been celebration of their discomfiture at this moment, but it won't last. I believe that even if the Ilkhanate seeks to convert its subjects--which is counterindicated for them if they want to survive as political rulers--Islam as a folk religion will persist in Persia, Mesopotamia, Arabia and northern Africa. And probably in the Steppes of central Asia and spread into India and Nusantara as OTL, while advancing in Africa. It may be that the relationship between the Sunni and Shia are reversed--the latter I believe are better set up to survive as a dissident more or less persecuted population out of step with the religious fashions dominating the central government, and might therefore be positioned to dominate Islamic orthodoxy once the Ilkhans falter or the Rhomans lose control of some major tract. Arabia itself will be difficult to control and Mecca remains the center of world Islam. I expect a major Islamic revival in the region of Persia, Afghanistan, perhaps Central Asia and almost certainly Mesopotamia to link up to its stubborn persistence in Arabia and in the Saharan peoples.
And of course the author may fully intend that the Hungarian dynasty is not going to guarantee the permanent survival of the Empire; it buys it a few centuries more of great power perhaps, but perhaps it is inevitable the Empire must go to pot sooner or later, and if it does, losing Anatolia again for instance, its further days may be numbered. I'd think the boundary between Orthodox and Latin spheres established here will tend to persist even if the Orthodox sphere suffers major weakening but perhaps some belated version of the OTL Ottomans will take Constantinople itself, which would leave the southern Rus tier and Hungary to quarrel over who hosts the Third Rome--not Moscow! Moscow would be in the Latin Russian zone.
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