The Middle Ages lasted nearly 1000 years. The era began when persecution of Christians in the Roman Empire ended with the Emperor Constantine in the early fourth century. Early Christian churches, tombs and catacombs from this period can still be visited in Rome. Constantine also established a new capital for the Empire far from Rome in the city of Constantinople (now Istanbul). The Empire after this time is known as the Byzantine Empire and is the last phase of the Roman Empire. The Byzantine Empire was Christian and lasted for a thousand years. Byzantine art is known for its ethereal mosaics, ivories, and metalwork. In Western Europe, extraordinary art was made by the Anglo-Saxons, under Charlemagne, and during the periods known as Romanesque and Gothic.