Answer:
He legalized Christianity and changed the capital
Step-by-step explanation:
Constantine—who ruled from 324 CE to 337 CE—made some significant changes to the Roman Empire. Two of these changes were the new capital at Byzantium and the new Christian character of the empire (Constantine legalized Christianity and eventually converted himself). These changes eventually created a distinct culture which would characterize the Byzantine Empire after the fall of the Western Roman Empire in 476.