Final answer:
Constantine moved the capital of the Roman Empire from Rome to Constantinople in 330 CE.
Step-by-step explanation:
Constantine moved the capital of the Roman Empire from Rome to Constantinople in 330 CE. He established a second imperial capital in Byzantium, which he renamed Constantinople. This new capital was strategically located near major trade routes, such as the Bosphorus Strait, which connected the Black Sea to the Mediterranean. The shift of the capital to Constantinople marked a significant eastward focus for the Roman Empire.