The Byzantine emperor Justinian I (482–565) initiated the reconquest of Italy to the empire, which made Venetia a Byzantine province under the Exarchate of Ravenna.
Why did the Lombards decide to invade Byzantine Italy in 568? A popular story was the Byzantine general Narses, who had just retaken Italy for the empire, invited them. Was Narses a traitor to the empire?
This document is the earliest description of the translation of St Mark to Venice in 827–828, and also of early Venice. This is a translation by René Seindal.
In late Antiquity the north-east of the Italian peninsula suffered many invasions. The wars caused people to move to the safer lagoon areas, and hence to the foundation of Venice.