How did the military expansion of Rome, under Justinian, revive the Roman Empire?

in the Byzantine Empire? What was the legacy left through this military expansion?How did the military expansion of Rome, under Justinian, revive the Roman Empire?It was not much the expansion of the Rome, but in continental Europe it is called expansion of the Byzantine Empire. It was driven by a desire of Justinian in reviving the territories of the Roman Empire in the West but not restoring the power centered in Rome. The political, cultural, and economical center of the Justinian Empire was in Constantinople that also was the source of his support. The Justinian had several objective, where he wanted to eliminate the barbaric threats coming from the Danube into the Byzantine Empire, removal Germanic government from Italy, destroy naval power of Vandal state that controlled Mediterranean. However, at the same time, while his ambition were driven to impose his only christian statehood into already early medieval and christian states of the West, Justinian was losing a war with Persia. During the Iberian War with Persia, Byzantine forces were defeated, the Antioch was sacked and the country signed peace at the cost of 11,000 pounds of gold. This drove Justinian to intensify a war in Italy, which lasted till his death and destroyed the ancient civilization for good. At the peak of this empire, the state managed to hold on Byzantine territory were around eastern Mediterranean, Italy, Greece, Balkans and Northern Africa. Some Spanish territories were also became under control of Byzantine Empire.



So, Justinian had tried to revive to some extend the Roman Empire to include the territories of the West, but was far from the political model of the late antiquity ruled from Rome. Any case, his military ambitions were short lived and bankrupted the state. Soon after his death, the precious control of Italy felt to Langobardians, and the fruit of victory was gone. Persian intensified attacks and Egypt, Levant and central Turkey, and they even felt off the Byzantine hands. This weakened local bonds of the provinces with Byzantine and were rather welcoming the Arab invaders with a new religion. The Slavs had permanently occupied central Balkans, while Avar khaganate severed important land route via Danube to Western Europe and Rhine. Persians together with Avars were 50 years after the death of this despotic ruler setting a siege to his capital. The policy of restoration of the empire was not dealing with realities of the situation and had devastating impact on the health of the state all together.