London is a place.
A capital city ( or simply capital ) is the municipality exercising primary status in a country , state , province , or other region , usually as its seat of government . London [ ˈlʌndən ] is the capital and most populous city of England and the United Kingdom . London is a leading global city in the arts , commerce , education , entertainment , fashion , finance , healthcare , media , professional services , research and development , tourism , and transportation . A report by the McKinsey Global Institute published in 2012 estimated that London had a city GDP of US$ 751.8 billion in 2010 , compared to US$ 764.2 billion for Paris , making them respectively the sixth - and fifth-largest in the world . London was the world 's most populous city from around 1831 to 1925 .