It forms the London region. Greater London is the administrative boundary for London, and is organised into 33 local government districts: the 32 London boroughs and the City of London, which is part of the region but forms a separate ceremonial county.

London has been a major settlement for two millennia, and was originally called Londinium, which was founded by the Romans. The City of London, London's ancient core and financial centre—an area of just 1.12 square miles (2.9 km 2) and colloquially known as the Square Mile—retains boundaries that closely follow its medieval limits.

The area of Greater London includes areas that are part of the historic counties of Middlesex, Kent, Surrey, Essex and Hertfordshire. London's status as the capital of England, and later the United Kingdom, has never been granted or confirmed officially—by statute or in written form.

The East End is the area closest to the original Port of London, known for its high immigrant population, as well as for being one of the poorest areas in London.