The Roman conquest of Britain was the Roman Empire's conquest of most of the island of Britain, which was inhabited by the Celtic Britons. It began in earnest in AD 43 under Emperor Claudius, and was largely completed in the southern half of Britain by AD 87, when the Stanegate was established. The conquered territory became the Roman province of Britannia. Attempts to conquer northern Britain (Caledonia) in the following centuries were not successful.

Aulus Plautius was a Roman politician and general of the mid-1st century. He began the Roman conquest of Britain in 43, and became the first governor of the new province, serving from 43 to 46.