London (England), city, capital of the United Kingdom. It is situated in south-eastern England at the head of the River Thames estuary. Settled by the Romans as an important shipping point for crops and minerals, it gradually developed into the wealthy capital of a thriving industrial and agricultural nation. The expansion in the 19th century of the British Empire increased London�s influence still further. Since World War II the city�s prominence on the international stage has diminished, but it remains a flourishing financial centre and home to one of the world�s most important stock exchanges., Havering, Hillingdon, Hounslow, Kingston upon Thames, Merton, Redbridge, Richmond upon Thames, Sutton, and Waltham Forest.