 Justinian was born in Tauresium around 482 . A native speaker of Latin ( possibly the last Roman emperor to be one ) , he came from a peasant family believed to have been of Illyro @-@ Roman or Thraco @-@ Roman origins . The cognomen Iustinianus , which he took later , is indicative of adoption by his uncle Justin . During his reign , he founded Justiniana Prima not far from his birthplace , which today is in South East Serbia . His mother was Vigilantia , the sister of Justin . Justin , who was in the imperial guard ( the Excubitors ) before he became emperor , adopted Justinian , brought him to Constantinople , and ensured the boy 's education . As a result , Justinian was well educated in jurisprudence , theology and Roman history . Justinian served for some time with the Excubitors but the details of his early career are unknown . Chronicler John Malalas , who lived during the reign of Justinian , tells of his appearance that he was short , fair skinned , curly haired , round faced and handsome . Another contemporary chronicler , Procopius , compares Justinian 's appearance to that of tyrannical Emperor Domitian , although this is probably slander . 
