Justinian I, traditionally known as Justinian the Great and also Saint Justinian the Great in the Eastern Orthodox Church, was a Byzantineemperor from 527 to 565. During his reign, Justinian sought to revive the empire's greatness and reconquer the lost western half of the historical Roman Empire. Justinian's rule constitutes a distinct epoch in the history of the Later Roman empire, and his reign is marked by the ambitious but only partly realized renovatio imperii, or "restoration of the Empire"...
(wikipedia)