London is the capital of England and the United Kingdom (UK). It is the UK's largest and most populous metropolitan area. A major settlement for two millennia, its history goes back to its founding by the Romans, who called it Londinium.London's core, the ancient City of London, the square mile financial district, largely retains its mediaeval boundaries. Since at least the 19th century, the name London has also referred to the metropolis developed around it. Today, the bulk of this conurbation forms the London region and the Greater London administrative area, with its own elected mayor and assembly.