Basically, what if Ottoman Rumelia never successfully expanded beyond its “core” in Thrace, with the rest of the Balkans remaining occupied by independent Christian kingdoms?
I think you make a good point about balance - if the Ottomans don't expand across the Balkans then someone will manage to build a credible threat to them and put Istanbul under siege - this happened multiple times to the Byzantines.Interesting idea. I'm not sure it's plausible. The idea of a country/empire *choosing* not to expand pretty much wasn't invented yet. Limitation of European Turkey to Thrace would depend on a fine balance of the Ottomans being contained but not destroyed by Balkan Christian states of exactly the right strength.
What kind of profile could this Ottoman state have in Asia? I would think that for "balance" reasons alone it couldn't really get beyond Turkic Anatolia and the Taurus mountains. But do you think it could get further and imitate the historic Ottoman conquest of the Mameluke Middle East?
Well, of course, i'd wager this scenario would involve some more political and economic intransigence or conservatism by the Ottoman political establishment which hinders its efforts at expanding into all of the Balkans. Would be an interesting set of possible events, though, especially if they can play the Balkan Christian kingdoms against one another to prevent an united crusading front from forming -- there's plenty of disputes to keep, say, Wallachia from allying with the Bulgarian principality, or the latter from allying with the Serbians...Would it need to be exactly Thrace or can we give or take in some areas? I am wondering about mountains and if some areas would be vulnerable to either attack or to people leaving. The Ottomans relied upon the Balkans for a great deal of their tax money as well as slaves (apparently part of why they might not have forced conversion on the people, as they could seize their kids as workers and charge them all higher taxes. Just some sources I read suggested it, I can’t say for certain myself.) Here I see the Christians fleeing Thrace completely as, unlike in the later Ottoman Empire when they ran all of the Balkans, here they have somewhere to run too. Come to think of it though, IOTL the Ottomans controlled the greater Macedonia region as well as Thrace and some other places before they managed to seize Constantinople. We will need to take that into account. Also, will they even manage to expand into the Arab world? They might have a degree of control over the Black Sea Trade here but without Egypt and the Levantine they cannot nearly monopolize the lucrative spice trade to Europe.
Would it need to be exactly Thrace or can we give or take in some areas? I am wondering about mountains and if some areas would be vulnerable to either attack or to people leaving. The Ottomans relied upon the Balkans for a great deal of their tax money as well as slaves (apparently part of why they might not have forced conversion on the people, as they could seize their kids as workers and charge them all higher taxes. Just some sources I read suggested it, I can’t say for certain myself.) Here I see the Christians fleeing Thrace completely as, unlike in the later Ottoman Empire when they ran all of the Balkans, here they have somewhere to run too. Come to think of it though, IOTL the Ottomans controlled the greater Macedonia region as well as Thrace and some other places before they managed to seize Constantinople. We will need to take that into account. Also, will they even manage to expand into the Arab world? They might have a degree of control over the Black Sea Trade here but without Egypt and the Levantine they cannot nearly monopolize the lucrative spice trade to Europe.