Don't you think that they would have been eventually tempted to promote the Archbishop of Cologne to a quasi-papal state in order to "relocate" papcy from Rome to i.e. Cologne? Specially if Rome falls to the Lombards and they ransack the city.
Well, the short answer would be "no", giving Cologne had no archbishop at this point.
More seriously, I don't think you really understanding how Latin churches worked out in Early Middle Ages : long story short, the national councils were gathered by the political power (the king usually, while more local synods gathered by largely autonomous dukes aren't unheard of) which made "national churches" being largely autonomous from each other, but they still hugely depended on roman pontifical legitimacy that if it was largely moral, dogmatic and symbolic (but not just this : pope had an important degree of autonomy in religious matters at this point) matters.
As long as you don't have any claim to imperium over all Christiendom as Carolingians went for IOTL, there's strictly no reason to attempt a rush for Papacy control : and even less to try for a counterfeit pope that would probably make illusion for 2 minutes.
Romans, then Ottonian/Salians could do that because they had their claim to imperium over Christiendom at least technically acknowledged. Any one else would just look as an idiot, and his own bishops would probably go "well, maybe we should support one of his rivals instead".
But then the Empire would be reduced to an Italian patch, unless they could crush the Lombard Kingdom. If the see is set back to Ravenna, it would be hard to control Sicily and Africa from there.
Not it wouldn't : with Roman Italy (that still represented a good chunk of the peninsula : it wasn't reduced to a patch yet ITTL) you'd have to count Roman Africa, Roman Greece and possibly Roman Thrace and western Anatolia in the reduced empire.
It's important, in order to have a reasonable expectation about this scenario, that Romans still had the upper hand in maritime matters. Meaning they had far more projectible capacities than all Romano-Barbarians taken together.
I don't see what's the difficulty there : Rome would have the military, political and fiscal resources to not only prevent Lombard take over for the forseeable future, but as well to gain back some foot in the western Mediterranean basin because there's no good chance for any other entity in the region to really prevent them to do so (not that it would be that of a good idea for Romans to attempt that at any cost, tough).
Ravenna itself is a good strategical point hence
why it hold out so long IOTL, especially when it comes to combined fleet/land maneouvres. Now Ravenna is only the most obvious choice, and one of the most sensibles strategically and politically if the emperors choose to relocate their court in Italy. Among the other choices, you'd have Bari or Reggio in southern Italy but I feel they would be to uncentered to be really efficient on the long run, and these were located on a narrow coastal band when
Ravenna wasn't.
I agree, but then the Empire becomes a more peripheral entity.
Again : fleet, ressources, relatively strong presence in Italy and Greece. It would probably as peripherical in the region as Carthagians were during Antiquity or Vandals two centuries earlier.
If something, as for Romano-Barbarians kingdoms are concerned, Roman Empire just became
less peripherical.
At least Sicily looks like a safe land where all the Byzantine 'refugees' could feel like home, due to its Greek-Latinness.
THat's another AH.com meme that needs to die slowly and painfully : most of the historical "Greekiness" of southern Italy does come from medieval times, due to the progressive hellenization of the empire. Don't get me wrong, you had an ancient Greek presence but it was limited to the coast and virtually absent in the hinterland.
If something, the imperial court (largely in the continuation of late Antiquity Romania, meaning not that hugely hellenized) may feel more at home in Italy, if we're about cultural closeness.
They could control Africa from there, but the risk of a Lombard full takeover of Italy is very high in this case.
Lombards took control of Italy quite slowly and while Constantinople was busy...basically everywhere else.
With an ERE that, willy-nilly, have to focus on its western provinces and will be much more wary about what happens in Italy because they won't have much other places to be wary about, it's dubious that Lombards will somehow go Blitzkrieg on Romans.
In order to cut short to some misunderstandings : no, I'm not saying Romans would be bound to reconquer Italy at the latest. But they'll be in a better position to deal with Lombards ITTL. There's an equivalence to be made on how the Empire of Nicea, forced to focus on Anatolia because they had no other choice, actually managed to do better in the region than Byzantines did before the Fourth Crusade.
I think that keeping all Greece is complicated.
If we're thinking about modern Grece boundaries, I agree : you'd still have a Roman presence up to Thessalia and coastal Thrakia and Epirus, but the rest is going to fall.
with Persian patches mixed with Roman patches. If the ERE does not recover, these Roman patches are likely to fall one by one with the pass of time.
As said above, Persians simply didn't were interested on European parts of Romania. As long Rome was unable to intervene in Middle-East in any kind of significant fashion, Sasannians were content : their own geostrategical focus was much more centered on the control of south-western Asia than bullying Rome for the evulz.
And even Sassanians knew how much of a problem it would be to manage territories on the other part of the sea without a big fleet in the region, especially when it was about ruling clearly hostile populations (no huge heterodoxial groups in Europe to make friends with as in Syria or Palestine).
Of course it's doable, but I find it hard to succeed in the long time.
Again : fleet, ressources, military. They could fail at it, of course, but there is as much reasons for the Empire to survive on this as it did on a really limited territory during the VIIIth/IXth centuries.
Probably in this case Avars would try to do the same and outcompete Romans.
Avars weren't an empire as were Persians or Romans, or even a institutionally structurated ensemble as Franks : it was an hegemonic confederacy, meaning that it was less about projection of political power (including military) than the capacities of the core group(s) to impose its own authority to junior partners of the hegemony. IOTL it declined because (among other things) the Avar prestige among slavs was significantly reduced before their defeats and the lack of redistributive loot.
ITTL, it may hold more by plundering Balkanic Romania, but giving Avar would have played no role in the 617 defeat (contrary to the 626 siege), they would end relatively empty-handed.
Meaning that their hegemony, while it won't fall apart, isn't going to transform japanese-mecha style into a superpower : I'd go with a less important decline, but still some form of stagnation for a while, a bit like the Bulgar Khaganate went in the IXth century after its big takeover.
Well, southern Gaul was the backyard of both Visigoths (who already held Septimania) and Lombards and they had obvious interests in this región.
I'm not sure if you know much the situation of Gondovald's revolt actually : basically when I say southern Gaul, I don't mean "mediterranean coastal Gaul", but southern half of Gaul up to Lower Loire basin (on which visigoths were fairly absent since the early Vth century).
Not only the visigothic province of Gaul was increasingly autonomous at this point (it was often specifically mentioned as not bound to obey counciliar obligations), but Gondovald's revolt is part of a system of alliances that concerned a general reshuffle in politics between southern Spain and Frankish Germany. I won't go into details : they're present if you click the link and read the post.
But suffice to say that because Goths never really attempted a move North of Pyrenées since two centuries, doesn't mean they didn't have huge ties with southern Gallic ensemble, even if by proxy : a lot of families in their province of Gaul had huge ties with Aquitain/Auvergne ensemble for exemple, and Aquitain policies are hard to understand if you don't point to how the bilateral relation in Vasconia didn't played out.
(Long story short, as I don't intend to translate my short memory on transpyrenean relations in Late Antiquity : these tended to form a one-way link, roughly following trade, and then court, roads from Spain to Gaul or from the province of Gaul to Spain. While visigothic tremisses are hard to find, being probably melted on arrival, but that associated with the early al-Andalusian coinage found in Gaul indicate that Visigoths were probably quite present on the flux between western mediteranean basin/Aquitaine/Atlantic)
But 7th century Visigoths did not care about matters in Italy, Neustria or Bavaria.
And it doesn't have anything to do with, for exemple, the fact they didn't bordered either of these?
We can't say both that they were overshadowed and less devellpped than the Merovingian ensemble, and then blame them to not act exactly as Merovingian did.
Visigoths only held Septa (Ceuta) in North Africa and even this issue is debatable.
While I agree the question of visigothic presence in North Africa is blurry at best, and that we should probably say "sphere of influence" when it comes to IOTL North Morroco, that they intervened in some form or another is undisputable, as were the relatively strong links between Roman Africa and Visigothic Spain (culturally, but economically as well).
The Papacy was uncomfortable with Arian Lombards since the late 6th century.
Rather than Arians, we should say Homeans.
The distinction is important, as Homeism was far less radically distinct from Chalcedonian beliefs (at the point that when one switched side, it wasn't considered as a conversion, and didn't required a baptism) : in fact, it was purposely vague about dogmatic issues, and eventually relatively compatible (with an increasing mix with Orthodox beliefs with time, would it be only because Barbarians could switch to Niceanism to Homeism or the reverse : see Suevi or Burgundians).
Not that the Pope wasn't incomfortable at the prospect being dependent from Lombards, of course : but one shouldn't exagerate the differences. IOTL, in the VIIIth century, Papacy found some sort of modus vivendi with Lombard (Ductatus Romanus being largelty autonomous at this point) that was backed by the possibility of a Byzantine intervention if it was broken.
Of course IOTL, Byzantines were unable to do that, and Rome had to find another champion.
ITTL, that said, Byzantine could very well support roman Papacy : giving that they're closer to Rome they were since centuries, it's even dubious you'd see the pope having its own territorial policy (he would rather be much more the relation between the Patriarch and the Basileus IOTL)
The Franks already warned Lombards to do not intervene in Rome, but Visigoths did not care at all, even after their conversion to Catholicism.[/QUOTE]