From c. 300 CE, as Christianity spread, the realism of Greek and Roman art was abandoned. Representation of deities as if they were ordinary people was perceived as idolatry.
After declaring Christianity a legal religion in 313, the Roman Emperor Constantine transferred the capital of his empire from Rome to Byzantium, renaming it Constantinople. Byzantine art developed there from c. 330 to 1453. Deriving from elements of Greek, Roman and Egyptian art. Byzantine art expressed a strong sense of order; artists excluded nudes and narrative images as they created to tell viewers about God, saints and the scriptures.
Along with Christianity, Byzantine art spread to other places, including Ravenna, Venice, Sicily, Greece, and Russia.
Surviving examples of Byzantine art include ...
Decorative, flat and stylized icons of holy figures predominated, with artists remaining anonymous. The veneration of God mattered, not individuals