The conquest of Britain by Claudius in 43 AD was partly a military operation and partly a political one. Claudius, who had come to power in dubious circumstances and had never held military command, needed a military triumph to establish his legitimacy. Britain provided it: geographically distant, notoriously difficult, and available for a convenient set-piece triumph.

The actual conquest was accomplished largely by the generals Aulus Plautius and the future emperor Vespasian. Claudius arrived for a brief visit to witness the capture of Camulodunum (Colchester) and then returned to Rome for his triumph. The operational commander and the political beneficiary were different people.

The subsequent history of Roman Britain is one of the better-documented Roman provincial stories, partly because of the quality of the archaeological evidence (Vindolanda tablets, London inscriptions, road networks, fort excavations) and partly because the British frontier proved persistently difficult to manage.

Hadrian's Wall (begun 122 AD) and the Antonine Wall (begun 142 AD) represent two different answers to the same strategic problem: where to draw the frontier. The eventual Roman decision to abandon the Antonine Wall and maintain Hadrian's Wall as the permanent frontier reflects a pragmatic assessment of the costs of holding the far north against persistent resistance.