He took Carthage back. He even took Rome back from the Goths, although not for long. And he's responsible for the building of one of the great churches of all time, which is now a mosque, the Hagia Sophia, or Church of Saint Wisdom. So after one of those sporting riots destroyed the previous church, he built this, which with its soaring domes became a symbol for the wealth and opulence of his empire. The Romans were remarkable builders and engineers, and the Hagia Sophia is no exception. A dome its equal wouldn't be built for another 500 years. But you'd never mistake it for a Roman temple.