Answer:
Justinian is considered one of the most important rulers of late antiquity. His long reign marked an important phase in the transition from the ancient Roman Empire to the Byzantine Empire of the Middle Ages. On the other hand, Justinian gained formative importance for legal history as he commissioned the compilation of Roman law, later known as the Corpus Iuris Civilis.
During his reign, the empire became increasingly sacralized. This destroyed the last remnants of the fiction once created by the principate that the emperor was only a primus inter pares. In the military field, he succeeded in long wars against Ostrogoths and Vandals, retaking large parts of the lost Western Roman Empire.