what was the capitol of the roman empire
Constantinople
Western Roman Empire
Under his rule, the city of Byzantium – only recently re-founded as Constantinople – was fully developed as a capital.
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Western Roman Empire [SEP] Further divisions
The West was unified in 340 under Constans, who was assassinated in 350 under the order of the usurper Magnentius. After Magnentius lost the Battle of Mursa Major and committed suicide, a complete reunification of the whole Empire occurred under Constantius in 353. Constantius II focused most of his power in the East. Under his rule, the city of Byzantium – only recently re-founded as Constantinople – was fully developed as a capital. At Constantinople, the political, economic and military control of the Eastern Empire's resources would remain safe for centuries to come. The city was well fortified and located at the crossroads of several major trade and military routes.