Epicureanism, founded in 307 BC, was by far the most successful form of deism in the ancient world, which naturally spawned many atheists. However, it remained somewhat marginal until rendered extinct by Stoicism, Neoplatonism, and Christianity in Late Antiquity. IOTL, Epicurus directly told his...
The huge problem for Egypt at the time was that the country failed to reunify in time, which allowed empires based in Mesopotamia to expand into the Levant and unify the Fertile Cresent. The Third Intermediate Period lasted nearly four hundred years, which was extremely long compared to the...
The state of Christianity in the West shouldn't be underestimated either, the Franks are on the rise and the formation of the Carolingian Empire is right around the corner. France and northern Italy would become the new center of Christianity; and whoever controls both would be viewed as the...
Is there any other reason why some reformist sect would become so popular that the Emperor himself adopted it? The problem also arises of why Zoroastrianism never spread into non-Iranic regions while Christianity directly overtook the political center of the Empire.
To answer OP's question, I would have to agree with @History Learner that Islam would be significantly influenced by Neoplatonic philosophy, best embodied in the current-day Ismai'ilis. Likewise, they'd be significantly much more influenced by Greek customs and culture. Since the politics of...
As much as I'd like to see a Muslim Russia, I'd have to agree with the fact that Vladimir adopting Orthodox Christianity was inevitable. The Byzantines were coming close to their absolute apex as an empire at this time (Macedonian dynasty and Basil II), and it's hard to see the Rus not choosing...
The huge problem with this is that the Greco-Roman world had been moving to monotheism gradually since the time of Plato (5th century BC), which arguably led to the inevitable adoption of Christianity. Everyone regarded the myths as exactly that--myth and superstition. At best, they were...
Also something to take into consideration is that the Western Empire was positioned horribly to defend its holdings. Evidently they tried to fix this IOTL by moving the capital to Ravenna, but it didn't work in the long run. They would either have to expel the Vandals and move over their base to...
Interpretatio Romana is exactly what you described: Romans equating foreign gods, such as Woden and Thor, with their own, Mercury and Hercules. The problem with that is that these gods have clearly conflicting roles, relations, and the mythologies in general were wholly incompatible with one...
The problem is that in Celtic cultures, druids were prohibited from writing down any oral tradition. In the case of the Slavs, written language basically arrived with Christianization, which results in the same problem.
Although it overlaps with the Palmyrene Empire, I've never heard of a Romano-Egyptian breakaway establishing its independence with the capital itself in Egypt rather than Syria.
The most evil state was clearly the Assyrian Empire; they were built solely on fear. Many Assyrian kings had monuments erected gloating about how they flayed captives and burnt their children alive.