For the ancient Romans, Britain was on the edge of the known world, beyond the bounds of the Ocean. In the Roman imagination, conquering Britain always had something of the magical and mythical about it. In 55 and 54 BC, Julius Caesar attacked Britain twice but failed to establish Roman control. In AD 43, the emperor Claudius launched the definitive invasion of Britain. His general Aulus Plautius won a pitched battle near Camulodunum (Colchester, Essex). Within a few years, most of southern Britain was in the hands of the Romans. Britain remained a Roman province until the early fifth century AD, an occupation which transformed the culture of the island.
This coin celebrates Claudius' triumph over Britain. The back shows a triumphal arch, of the sort erected by Romans in honour of a victorious general, rather like London's Marble Arch or the Arc de Triomphe in Paris. On the top we see Claudius on horseback with two trophies of weapons either side of him. The letters on the arch read DE BRITANN, which is the Latin for '[A triumph] over the Britons'. A fragment of the arch can still be seen at the Capitoline Museum in Rome.