The ancient name for Istanbul is Byzantium, later known as Constantinople. Founded by Greek colonists around 657 BC, Byzantium was strategically located on the Bosporus Strait, serving as a key trade hub between Europe and Asia. In AD 330, Roman Emperor Constantine the Great refounded and expanded the city, renaming it Constantinople and making it the capital of the Eastern Roman Empire. Its strategic location, rich culture, and political significance enabled Constantinople to thrive for centuries until it fell to the Ottoman Turks in 1453, after which it was renamed Istanbul and became a focal point of the Ottoman Empire.