Assay: German-Romans vs Slavic-Romans in the 7th-8th centuries

I wrote this assay in a encyclopaedic style:

"In 618 Constantinople fell to the Sassanians and the last Eastern Roman Emperor, Heraclius, died when trying to escape to Adrianople with many other Byzantine noblemen, who were mostly captured as this later city was also captured by the Persians shortly after.

The Sassanians were not interested in the full incorporation of the area of the Bosphorus in the Empire, so they let their Avar and Slavic allies to resettle the area evacuated by the Byzantines. This region was reorganized as a client state, the Kingdom of Roma Sclavona or Slavic Rome, tied to the new Persian vice-royalty of Chalcedon.

The Byzantines who escaped the Persian invasion sought refuge first in Greece, but due to its vulnerability, the surviving army and fleet preferred to travel further up to Sicily. The Empire then lacked of an Emperor and a capital city, and different claimants to the throne appeared immediately and started diverse minor fights between their factions.

The Sassanians imposed Nestorian patriarchs in Constantinople, Antioch and Jerusalem. In 634, the newly formed Arab Caliphate attacked the Sassanian Empire, but they were not able to make any progress in Syria and Mesopotamia. However, they conquered Palestine in 639 and passed to Egypt in 642 and Cirenaica in 644, and after that, renewed their attacks against Persian Mesopotamia.

The trouble of the Sassanian-Arab War benefited the Slavic Roman state, which expanded into the vice-royalty of Chalcedon up to central Anatolia and captured Iconium in 647. When the Sassanians finally managed to crush the Arabs in 651, the Slavic Roman state had ‘recovered’ most of Anatolia.

In 654, a civil war in the Sassanian Empire made one of the claimants of the Persian throne to ally with the Slavic Romans in order to win the other factions. The new Emperor granted the legal control of a large vice-royalty (including the Bosphorus, Anatolia, Syria and Cyprus) to the Slavic Roman nobility. However, this new Emperor was overthrown in 669 by a rival faction, and the Slavic Romans pushed then for full independence. The result of the 669-672 war was in favor of the Slavic Romans, who achieved complete independence and gained more Christian-majority territories like Armenia and Upper Mesopotamia. The rest of the former Empire was reorganized as a Zoroastrian Iranian Kingdom.

Meanwhile, the free Roman territories had badly coalesced around the authority of the Consul of Carthage first and since 665, the self-proclaimed Duke of Sicily. The Pope had refused to recognize any claimant to the Imperial vacancy, because all of them lacked of any legitimacy or sufficient authority. Now that the Nicene/Catholic Church had cut any relation with the new Nestorian Church imposed in the East by the Sassanians, the Pope remained the only relevant figure in the Church who could effectively mediate in the Imperial succession controversy.

In 681, the Arabs attacked the Roman province of Africa and some of the Roman forces located there evacuated and passed to Sicily. However, the troops under the leadership of a local Roman noble with Vandalian descent opted for offer resistance to the Arabs in the region of Annaba and stop their way to the West. The Romans successfully resisted and the Arabs finally retreated to Carthage. The local noble was acclaimed as Duke of Vandalia and launched a counter-attack in Arab-occupied Africa. The Arab troops tried to pass to Sicily but they were halted by the Sicilian militias. Finally, the local noble besieged Carthage in 685 and the Arabs surrendered. After the huge defeat, the Caliphate retreated to Cirenaica and abandoned the project of expanding westwards.

The military success of the local noble made him eligible to the title of Emperor, thus he was crowned by the Pope in 689. The Slavic Roman Kingdom did not recognize such legitimacy and the Nestorian Patriarch of Constantinople crowned his own candidate shortly after. The Romans in Greece did not recognize either and formed their own entities, subdued to the Duke of Athens.

Regarding the German-Roman kingdoms, none of them recognized the authority of the new Emperor. The Roman territories (where the authority of the Emperor was actually recognized) were dramatically reduced to Sicily, the Duchies of Rome and Vandalia (Africa) and some patches in Italy (Ravenna, Naples…). All the approaching to the Roman-Greek states were futile.

In 722, the Franks launched a great-scale war of invasion against the Lombards. This war endured for many years, but in 735 the Franks arrived to the vicinity of Rome. The Roman Empire had being declining since the victory against the Arabs and it was no capable by then to face the Frankish threat. The current Roman Emperor was weak and offered the hand of his daughter to the Frankish King with the aim of avoiding war. The Roman Emperor died shortly after without an apparent heir, so the Pope decided to crown the baby son of the Frankish King and the Roman princess.

This baby will inherit also the title of King of the Franks and the Lombards, after his father subdued the later. Thus, this was the first Emperor of the Romans and the Germans, opposed to the Emperor of the Romans and the Slavs sitting in Constantinople."

Looks plausible enough? Is it TL-worthy? Thoughts?
 
Please, please, please, please, please, please. This sounds absolutely amazing.

One question what of the Kyiv'ska Rus' territories that will begin to form an East Slavic Empire later on? Do they continue with such developments? If so how are relations between the two Slavic states? Considering the actions of Sviatoslav "the great" how would these two Empires interact?
 
OK, thank for your positive comments! :)

I'm planning to start this TL after Christmas, because I will have free time for writing then. Before that, I still need to do some further research and also need to perform some plausibility checks.
 
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