Epilogue
or
How I planned things to end
The East
In Sassanid Persia, the burden of paying tribute to the Hephtalites becomes so great that, eventually, there is a revolt against them and their puppet regime. While the fighting is still ongoing, the Romans decide they also want a piece of the pie and invade Mesopotamia, ostensibly to reinstate Khosrau. Eventually, the Hepthalites and their local allies defeat the rebels, only to leave much of the countryside in ruins, with entire regions in the south only nominally subdued, and Mesopotamia in Roman hands .
The fortunes of the white Huns then plummet as they find themselves unable to stop the migration of Turkic peoples into their homeland, since they were seriously overstreched holding down Persia. They linger on for a few years as the ruling class of Persia, only to be overthrown in a native rebellion (sponsored by the Romans) and thus cast into the dustbin of history.
This second civil war again causes much destruction to Persia’s urban culture, which then receives yet another blow when a combined Turkic and Roman invasion takes place. The northern nomads manage to establish themselves as overlords with Roman support, but this only lasts for the lifetime of the King who held his coalition together, so no more than a decade. Just like the Hephtalites, they too are ousted in a native revolt, which sees particularly heavy damage dealt to the Mesopotamian countryside (with Ctesiphon being sacked a number of times by opposing armies) as well as any remaining large cities in Iran.
In the coming decades, Persia finally manages to pick itself up, unite its disparate provinces and occupy the buffer states the Romans had set up in Mesopotamia. It is to no avail however, as the exhausted state is invaded and occupied by a coalition formed by the booming Arabian tribes to the south. Even though said coalition dissolves to infighting a couple of decades later, Arabs manage to hang on as the Persian ruling class, more concerned with ruling over their subjects or resisting invasions by central Asian nomads than aggressive territorial expansion. In the long run though, they eventually get “Persianised”.
In the initial outburst in the middle of the VII century, the Arabs also temporarily take Judeea from the Romans and intensively raid Syria, whilst to the west a civil war had been raging between the Romans. Unfortunately for the Arabs, the Roman civil war ends and Constantinople floods the area with troops, expelling them.
The Balkans
In the Balkans, the slow and steady process of recreating the area’s urban culture and infrastructure grinds forward. Occasional raids and invasions still happen, like the one in 559 by Huns and Kutigurs, but overall, these fail to disrupt imperial policy in the area. Constantinople gets to enjoy the benefits of a friendly hinterland populated by Latin-speaking Romanized Thracians.
Many years later, during the great Slavic migration, the area will get to see some particularly heavy fighting. While militarily the Slavs are eventually defeated after a two-decade-long war, demographically they still leave their mark of the Balkans south of the Danube, with numerous groups mixing with the local Romanized population. Though eventually assimilated, they still leave considerable influences. Many of them are also settled as slaves throughout the Empire.
North of the Danube, the Slavs completely assimilate the local Daco-Roman populations, and, with time and given the proximity to their advanced southern neighbor, they create powerful states. On few occasions, they pose existential threats to the Byzantines, other times they act as buffers between the Empire and the various steppe peoples advancing west: Bulgars, Magyars etc. Sometimes they resist these invaders, other times they are temporarily conquered only to expel them and, on occasions, they assimilate their conquerors.
Gaul
The Romans would never get to fully conquer Gaul again. The province is extremely far from the main centers of wealth and power and also truly devastated by the war Justinian initiated. While the Franks are temporarily subdued, and even a small scale expedition to Britain takes place, the power vacuum the war created draws in peoples from far and wide. Moreover, whenever there is a crisis, troops from northern Gaul are the first ones to be pulled back.
Goths, Burgundians, Bretons, Franks, Frisians, Saxons, various Germanic tribes (especially Lombards) come to settle Gaul and rule over bits and pieces of it. None of them manage to achieve any kind of hegemony that lasts more than the lifespan of the king that tried to establish it.
Only to the south, along the coast, does a thriving Gallo-Roman community develop.
Spain
Soon after the conquest of North Africa by the Romans, a succession crisis and civil war ensues among the Visigoths. Justinian decides to take advantage of this and sends an expedition. Some ground is gained, particularly along the coast, although victory continues to elude the Romans. However, instead of continuing a long and devastating war, a political solution is reached. Germanus, Justinians cousin and heir would marry the Gothic princess with the greatest claim to the throne, the Visigoths would submit but enjoy considerable autonomy (much like almost happened in Italy with the Ostrogoths OTL before Germanus unexpectedly died). The arrangement lasts for the lifetime of Germanus, and of that of his heir, Justinian II. Thereafter, the Visigoths break free. Sometimes their realm will be centralized under a strong ruler, other times divided amongst multiple claimants. In time, they merge, together with the local Hispano-Romans to create a new people.
Meanwhile, the eastern coastal regions of Spain (which will evolve into a much more “Latin” character) would remain a point of contention between the Visigoths and the Empire, much like Armenia was between the Byzantines and their eastern rivals, with both powers constantly trying to assert their religion and puppets over those of their opponents.
The Mediterranean and Religion
Places like Italy, Greece, Egypt, Anatolia and Syria go on to form the core of the Empire, and evolve a common identity, whose bedrock will be their common religion, and strengthend by strong trade links and tradition. While civil wars will still flare up on occasions, they will be more about control of the whole Empire rather than local independence
The ruling class will, in most cases by adept in two or three languages: almost all will know Greek, and many of them will also know Latin and the local language (should that be different from the first two). Legislation will continue to be published in Latin and Greek, and Church services would be performed in either one of these two languages.
Monothelitism will emerge as the dominant doctrine among these places, its place assured after its victory in the civil war that took place at the time of the Arab invasion of Judeea. The Pope will be just another of the main Patriarchs and will not enjoy supremacy over them.
Spain, Gaul, Britannia, Germania and Slavonia will adopt versions of Christianity that oppose Monothelitism, and develop independent Church structures, often subordinate to their local King.