The Roman Empire lasted from 27 BC until 476 AD, when it was finally conquered by a Germanic warlord named Odoacer. However, the Roman Empire had started a long period of decline long before the 5th century AD. By the time Rome fell in 476 AD it had been declining for a number of reasons. One of these was internal corruption. Another was successive invasions by Germanic tribes, including the Vandals and the Ostrogoths. Other major factors in its decline were the division of the Roman Empire by the emperor Diocletian and the moving of the capital to Constantinople by the emperor Constantine.