WORLD CIVILIZATION

Detailed explanation-1: -Constantinople (see other names) became the de facto capital of the Roman Empire upon its founding in 330, and became the de jure capital in AD 476 after the fall of Ravenna and the Western Roman Empire.

Detailed explanation-2: -Constantine moved his capital to Byzantium (later named Constantinople ) in 330 AD because the eastern part of the Roman Empire was becoming more important and he wanted a capital that was closer to the center. Also, the area allowed easy access to vast territories via the Marmara sea and the Danube river.