It does not have an official definition. The idea has its origins in 1720 as "That part beyond the Tower". By 1950 it was called East London and included all of Greater London east of the City of London and north of the River Thames. This area now makes up the London boroughs of Barking and Dagenham, Hackney, Havering, Newham, Redbridge, Tower Hamlets and Waltham Forest. It includes one of the highest ethnic minority populations in the country, mostly families of South Asian origin.
The East End of London is a subset of East London, corresponding to areas closer to the ancient City.
The early development of London eastward was caused by shipping on the River Thames. There were docks and shipbuilding. These industries declined after World War II. Felixstowe is now used as the main container port of southern England. East London is now an area of regeneration.
Areas further east developed in the Victorian and Edwardian eras following the expansion of the railways in the 19th century. In Tower Hamlets the population peaked in 1891 and growth was restricted to the outer boroughs. By 1971 the population had peaked in every borough and the entire area was experiencing population decline. By the time of the 2011 census this had reversed and every borough had some growth in population.