The Vandals adopted Arianism, a branch of Christianity that believed that Jesus Christ was not God, but a separate created being directly beneath God. This belief was in opposition to the belief of the main Christian group in the Roman Empire, which later grew into Catholicism and Eastern Orthodoxy.
Under their king, Geiseric, the Vandals settled in the Roman provinces of Numidia? and Africa in 428, when Augustine was bishop of Hippo. Their movement eastwards across Africa were halted when they were defeated by Byzantine? forces led by Belisarius? on behalf of the emperor Justinian I in 533.