In the remnants of the Roman Empire, cities of late antiquity gained independence but soon lost population and importance. The locus of power in the West shifted to Constantinople and to the ascendant Islamic civilization with its major cities Baghdad, Cairo, and Córdoba. From the 9th through the end of the 12th century, Constantinople, capital of the Eastern Roman Empire, was the largest and wealthiest city in Europe, with a population approaching 1 million. The Ottoman Empire gradually gained control over many cities in the Mediterranean area, including Constantinople in 1453.