Justinian was first appointed to military command in 550, when he, together with his brother Justin, were to accompany their father in his expedition against Ostrogoth Italy.
Yustinianus pertama kali diangkat menjadi komandan militer pada tahun 550, ketika dia, bersama dengan saudaranya Yustinus, akan menemani ayahanda mereka dalam ekspedisinya melawan Ostrogoth Italia.