Kingdom of the Lombards
After the fall of the western part of the Roman Empire (conventional date 476 BCE), the Ostrogoths invaded Italy and established the Gothic Kingdom (493–553). The Byzantine emperor Justinian I (527-565) decided to annex Italy to the Byzantine Empire. This led to the Gothic War (535–554) between the Byzantines and the Ostrogoths, which was won by the former. Byzantine rule in northern Italy was short-lived as the Lombards invaded northern Italy (568-73) except for the lagoons of north-eastern coast of Italy. Altinum eventually came under the duchy of Treviso of the Kingdom of the Lombards (568–774).