The Romans built a settlement at a key crossing point of the River Thames in AD 47-50, which was abandoned during the Iceni rebellion a decade later. After the Romans defeated Boudica, a military installation was put there, and the city rebuilt. Londinium, or Roman London, evolved into the capital of Roman Britain. The City of London was established in about AD 200, during the reign of the great emperor Septimius Severus, when the London Wall was laid around the perimeter. London served as a major part until the Romans left Britannica for good in the fifth century. The city lay in ruins for centuries, until its re-founding by King Alfred the Great in 886.–This is a silver denarius of Septimius Severus, who built the London Wall, establishing the City of London

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