Justinian I is traditionally known as Justinian the Great and also Saint Justinian the Great .
Justinian I ( [ dʒʌˈstɪniən ] Flavius Petrus Sabbatius Iustinianus Augustus , Φλάβιος Πέτρος Σαββάτιος Ἰουστινιανός , Flávios Pétros Sabbátios Ioustinianós ) ( 482 14 November 565 ) , traditionally known as Gustus Le Grand and also San Giustino Il Grande in the Eastern Orthodox Church , was a Byzantine ( East Roman ) emperor from 527 to 565 .
Justinian I